Subscribe to Breaking News emailsYou have successfully subscribed to the Breaking News email.Subscribe today to be the first to to know about breaking news and special reports.Officers stand in front of a YouTube sign near offices in San Bruno, California on April 3, 2018.Jeff Chiu / APBreaking News EmailsGet breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.Nasim Aghdam repeatedly aired her frustration with YouTube on online accounts and on a website linked to her, before she allegedly opened fire on the company’ headquarters in San Bruno, California on Tuesday.Aghdam, 38, was found dead on Tuesday from a self-inflicted gunshot wound after injuring four people during her shooting rampage, according to local police officials. On Wednesday, the police said they believed Aghdam was motivated by her anger with YouTube.YouTube policy changes in recent years have made it harder for video creators to earn money on the platform. YouTube has also narrowed what is considered acceptable — and monetizable — content, moves that have sparked heated criticism from some video creators.“We know that she was upset with YouTube, and we’ve determined that right now that’s the motivation we’ve identified,” San Bruno Police Chief Ed Barberini said, adding that it has not been determined whether her actions were related to terrorism.The Mountain View Police Department released a statement saying that Aghdam’s father informed them his daughter was in the area after “she made a series of vegan videos for her channel on YouTube and that the company had recently done something to her videos that had caused her to become upset.” San Bruno police identified the YouTube shooter as Nasim Aghdam, 38, of San Diego. Nasime Sabz Ye?il Nasim / FacebookAccording to a review NBC News conducted of Aghdam’s online account history, she posted videos to four YouTube channels, with most of her work focused on veganism and animal rights. Other videos featured bizarre parodies or exercise videos set to strange music. Her four channels collectively earned more than 9.2 million views on YouTube since she joined the site in 2010.Aghdam’s grievances with YouTube stemmed from changes made by the company to how it pays video creators for ads shown before or alongside their videos. Those changes, some of which occurred less than three months ago, included making it harder for video creators with smaller followings and view counts to make any money from their videos. Some in the YouTube community have criticized those changes.Aghdam’s issues with YouTube appeared to have swelled last year. A file in an image folder on Aghdam’s personal website showed what purported to be an email she received that appeared to come from an email account associated with YouTube’s legal support team in response to a complaint she levied on June 16, 2017. The picture is not displayed on Aghdam’s website, but was uploaded to an index folder containing all images hosted on the site.In the email, which was added to her website June 27, 2017, Aghdam complains of “discrimination and hatred problems against me,” alleging a “huge drop in views” after she began uploading videos in Farsi and Turkish. An email from NasimSabz.com. Nasim Aghdam opened fire at YouTube’s California headquarters on April 3, 2018 before turning the gun on herself. NasimSabz.comAghdam appended a message in a red font atop a screenshot of her purported interaction with a YouTube support account.”My email to youtube legal team. Subject is discrimination, but their response is about account activation!”YouTube did not respond to requests for comment from NBC News.Aghdam’s family confirmed her YouTube usage to NBC News on Tuesday. In a brief phone interview, her father, Ismail Aghdam, said the platform had “stopped everything and now she has no income.”Ismail Aghdam later told the San Jose Mercury News that his daughter “was angry” and “hated” YouTube.Charts on the analytics site SocialBlade show that Aghdam suffered a substantial decline in viewers and subscribers on her main YouTube channel in June of 2016. Aghdam opened several other YouTube accounts over the course of 2016 and 2017, all of which received noticeable drops in viewership within months of their creation.It’s unclear how much money Aghdam was making for her views, but SocialBlade estimated that she was making between $661 and $10,614 a year between her four YouTube accounts.“On YouTube, a creator can estimate that they’ll get somewhere between 25 cents and $4 per 1,000 views. These data points change from time to time and are not an exact science, but generally hold true for most channels,” SocialBlade CEO Jason Urgo told NBC News.A website registered in Aghdam’s name and a hub for her now deleted YouTube accounts, NasimSabz.com, prominently features several videos about YouTube demonetization under the heading “Youtube filtered my channels to keep them from getting views!”The section includes three active YouTube videos, one by vlogger Casey Neistat, another from a channel called “Bite Size Vegan,” and another by InfoWars writer Paul Joseph Watson.Watson and InfoWars, a website known to frequently spread conspiracy theories that was founded by Alex Jones, have posted dozens of YouTube videos and articles decrying what they deem to be “censorship” at YouTube. One of InfoWars’ videos on YouTube from last month is titled “These are the videos they want banned from YouTube” and has the “Internet censorship is here and it’s time to fight back.”InfoWars has amped up attacks against the tech giant since receiving two “strikes” against YouTube’s community standards. YouTube has said that it would ban InfoWars from YouTube if it has to issue a third “strike.”YouTube currently allows its users to monetize their videos through the YouTube Partner Program. The program now requires a channel to reach 4,000 watch hours over the course of the past 12 months and 1,000 subscribers to be eligible for partnership, according to YouTube’s help center.Those rules were put in place on Jan.16, 2018 as part of an effort to to weed out “bad actors” like spammers and impersonators, according to Variety. The prior threshold for a channel to qualify for monetization was 10,000 views.“This is part of an effort to strengthen our requirements for monetization so spammers, impersonators, and other bad actors can’t hurt our ecosystem or take advantage of creators, while continuing to reward those who make our platform great,” YouTube says in the post.Once a user meets the requirements, they must agree to the terms of service, sign up for AdSense, a Google program that allows publishers to run advertisements, and set their monetization preferences before submitting videos for review by the site. If approved, the channel can begin to make money.But YouTube’s monetization process was not always this rigorous.The “Adpocalypse,” what many major YouTubers refer to as the beginning of the site cracking down on who is and isn’t monetized, began in early 2017.Many content creators say the rules have been nebulous and some claim they often have videos demonetized that do not violate the company standards. Because of this, many YouTubers have turned to Patreon, a subscription service for content creators, or YouTube Red, a Google subscription service that costs its users $9.99 a month.Breaking News EmailsGet breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.Demonetization appeared to be a source of contempt for Aghdam, who posted at least one image to her website that noted she made $0.10 for a video that received more than 366,000 views.”Youtube filtered my channels to keep them from getting views!” Aghdam wrote on her website. “There is no free speech in real world & you will be suppressed for telling the truth that is not supported by the system. Videos of targeted users are filtered & merely relegated, so that people can hardly see their videos!”Aghdam appeared particularly motivated to spread her political views, specifically veganism. She wrote dozens of memos outlining her views that were accessible in non-public parts of a website registered in her name, NasimeSabz.com. In one of the memos, Aghdam likened terrorists to meat eaters, saying “only name those who murder humans terrorists and have closed our eyes on the crimes that are committed daily against animals.”“Most people hate terrorists (human murderers), but if they look at their own true faces in treating innocent animals, they will see they cause violence and murder just like terrorists, either directly or indirectly,” one of files on Aghdam’s website, labeled fa_humanityy.pdf, reads. “The whole world may mourn for the death of one person but ignores thousands of animals being tortured and killed every day!”Aghdam’s brief brush with YouTube fame came two years ago, when her videos were mocked by a Turkish YouTube star. A compilation of Aghdam’s videos, with underlyingary by the user Yorekok, received over 800,000 views.“In today’s episode, we have stocked enough nightmare fuel for years,” Yorekok said.Brandy Zadrozny contributed reporting.Breaking News EmailsGet breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.MORE FROM newsHave feedback?How likely are you to recommend nbcnews.com to a friend or colleague?0 = Very unlikely10 = Very likelyPlease select answerIs your feedback about:ContentDesignOtherPlease select answerLeave your email if you’d like us to respond. (Optional)Please enter a valid email addressThank you!Your feedback has been sent out. Please enjoy more of our content.We appreciate your help making nbcnews.com a better place.