There are separate webpages for creating a Facebook ad campaign (Ads Manager is one, plus there is a separate option with less features; I believe this is the Boosted posts function). The Ads Manager also displays a popup that the software might not work fi you have an ad-blocker enabled. For my devices, it’s slow and buggy in any browser except for Chrome.
The UI for managing Pages as a business is also poor. In the past (with previous Facebook Q&A forum posts documenting this), Facebook would automatically convert text posts by a Facebook page into a job listing, without asking for confirmation (!), making it unintuitive to undo. Separately, it also has limited categories for Facebook events (there is no category for educational events; the closest is the “Home” category).
Facebook has also removed certain popular features in the past, such as initially hiding, and then removing the feature to Share a post with the feature to “Keep the original post” (so only the link is shared, but not the post text that accompanied it by the original poster). The feature was lost due to a Facebook redesign, which is baffling because this reduced the likelihood of Facebook users to share content.
Maybe it’s different for larger customers (though I suspect they use the same tools), but the poor UI is frankly ridiculous for paying advertisers. Perhaps it does make sense, though; their competitor is Google Search and Display ads, which also have user interface problems (e.g. refusing to let you publish an ad set you’re willing to pay for, with very minimal messaging as to where exactly the error is, prompting multiple forum posts by other users). It’s effectively a duopoly, as other social media advertising channels are far less effective (maybe not LinkedIn, though LinkedIn is pricier), and newspaper ads are far more pricey (with higher minimum ad spend) with lower reach.