Email: Outlook UI and hotkeys are totally different from MacOS, Windows, and Web. Rules don't really work and are impossible to debug. Search is terrible. Threading is terrible (expands the subjects of each child message, but not their bodies... whyyyy).
Calendar: How the heck do you find an event you previously declined but changed your mind on? Why does Teams and Outlook both offer a calendar, with subtly different UIs and features, and the web interface is totally different yet again? It is incredibly slow (things take multiple seconds, like loading someone else's calendar, or clicking on an event it has to take time to load in the attendees...). The "suggested times" feature is hard to find and there's no visual guide (like a week view); also it again seems different between the apps.
Teams: Oh god. This... is what they came up with? It's sooooo slow on startup. It duplicates Outlook notifications. It is hard to find the meeting you're supposed to join when you first clicked on a join link, but then it asks you to login, etc. It's so much less feature-ful than Zoom, yet so much harder to use (and uglier) than Meet. Why do the chat rooms persist not only after a meeting but get resurrected later in the week, and why do they notify you for chats in a meeting that you're not even in. The share screen sidebar is atrociously hard to see to determine which window you're trying to share. Like... literally all the basics they got wrong, and this one software has the worst UX of anything I've seen.
Excel, Word, etc.: My god, the UI has gotten even worse, the forced OneDrive integration is terrible, etc...
I grew up using Microsoft stuff until Google started popularizing their online suite. In the years since, every employer except this most recent one has used Google and while it never struck me as particularly pretty, it was pretty easy to use for the most part. I was actually kinda curious to try the Microsoft stuff again, figured they had 20 years to catch up, it's gotta be better now, right? Nope. I've never hated a stack as much as this, even as a long-time Windows user... in fact it's going to be one of my questions for employers in the future, and a big red flag.
Sorry, I know I sound pretty agitated about this. Their software griefs me on a daily basis and is the single thing I hate the most about my job. It's just SO terrible. I guess YMMV, eh? I didn't realize there were actually people out there who preferred the Microsoft stuff... of the folks I've spoked to casually, all vastly preferred Google's implementations. But that's just anecdotal.
