LibreOffice is absolutely awful from an UX point of view. That’s enough to put me off personally.

If you’re an office expert you’d probably figure out how to use it, but for me I’ve only used an office suite maybe a dozen times in my life so I’m very new to it, and latest Office 2016 allows me to get started easily (the much-hated Ribbon UI works for me and is intuitive), where as I find myself Googling all the time to do even the basic stuff in LibreOffice.

LibreOffice suffers the same issues as Star Office and others alike, and I think this is a reflection of how people get rewarded by developing open source.

Adding new features gives you a lot of fame. Fixing bugs and improving things does not.

I don't think LibreOffice has an equivalent to OneNote, and I use the desktop client for that a lot.

Also, this might sound shallow to some, but the latest version of Office just looks a lot better than LibreOffice and I enjoy that.