Low pay: Unless you're an upper level leader or top sales person, Qualtrics pays about 10-20% below the market rate. This can be frustrating as an employee. Promotions outside of sales are very difficult and slow, despite what may be communicated. If you are starting in an entry level position, don't count on ever getting a real big pay day (again, unless you're a sales all-star). From what I understand they do this is in order to be more profitable to get a higher valuation when they IPO. Also they don't want employees who work there "for the money", but rather people who believe in the vision and want to be there for other reasons.
Hype to substance ratio: There's a LOT of hype from leadership around Qualtrics' future, how they're profitable, how they're a rocket ship, how they going to IPO, how they have amazing investors and a great board, etc. but much of the hype seems to be just hype and regular employees don't necessarily see the benefits of the company's "deep pockets" or unicorn-ness.
Politics: Most employees at Qualtrics are ambitious and young in their career and are striving to climb the ladder and move to the top. Unfortunately this leads to quite a bit of politics and ulterior motives. Lots of people trying to do whatever it takes to get recognized by the right people and lots of the time it's about who you can get tight with within the company and not always a meritocracy. Overall employees aren't treated as well as they should be and certainly aren't treated as the company's most valuable asset (unless you're a top salesperson).