I’ll admit to just being a front end user of the platform only so I am sure it framed my opinion—the UX was dreadful. The other thing that set the bad taste it was brought in as the corporate email platform by a company that acquired us and since I lead IT for our org (now a division) and corporate IT was across country and 3 hours behind, we caught the brunt of all the user complaints and support for the first half of the day until the help desk opened up.