Windows Movie Maker
Windows Movie Maker was the default video editing software for all Windows OSes from Me to Windows 8.1. However, a side effect of being the default is having little functionality, resulting in videos that look like they're straight out of 2006. The program is so basic and clunky that even a chimpanzee could figure out how to use it. All you have to do is drag and drop your footage into the timeline, add some cheesy transitions and effects, and voila! You've got yourself a masterpiece that no one will ever want to watch.
Being the default video editor on Windows for a time, it was completely free, which is great for low-budget wannabe filmmakers who can't afford/don't want to buy more advanced video editing programs, right? No. Any video made with Movie Maker will end up on YouTube with a bunch of dislikes. Depending on how "well" the video is edited (the best is below-average), the dislikes could come from a minority of people who hate anything made with Movie Maker to your video having ten times more dislikes than likes. So stop using Movie Maker and download a cracked version of Vegas Pro like everyone else.
In short, Windows Movie Maker is awful.