The culture is a bit click-y; lots of socializing / romantic relationships between staff outside of work. Feels like high school at times.
The product hasn't been best-in-class in a long time; not enough innovation to improve it or introduce newer, better ones.
They don't part ways with poor performers fast enough. I have worked for companies where it feels like you're on the A Team ... this feels like being on the B Team. There are certainly talented people at Moz, but there are also too many people coasting, which brings down the caliber of the whole team.