Significant overtime without warning or appreciation. I am a 9-5 type person, but have happily tolerated 9-5.30 in past employment or even later occasionally - preferably with warning. What I can't tolerate is receiving a lot of pressure to stay in until 8/9/10 with zero warning - which means you have to constantly flake out on friends and can't reliably make evening plans during the week. A sip of champaign after a successful delivery doesn't make up for that, and is one of the reasons I left that job.
Some ethical questions may be asked about minor elements of the product I could list two minor things here but won't - anyway, Google to see their customer reviews - they aren't all positive.
Senior management handle some incidents poorly and treat staff more like children than employees - unprofessional behaviours. I had to console some fellow staff who were involved in this. I was a shoulder for 2 or 3 others to lean on - tears, complaints, venting.
I had a major issue with my manager, which I could tell many others did too but everyone just put up with it. "Toxic boss" is the term, overly-dominating body language, de-moralising the team, taking credit, making an example of those who appeared to question his poorly-earned "power".. And also, pressure to work late. I don't understand how the company turned a blind eye to this individual, perhaps he had the right friends - or was a master manipulator. The main reason I left my job.
The company seems to have a strategy of push your employees to their limit (burnout) and then just get new ones in to replace them.
When I questioned the overtime to my manager, my team dedication came into question. I worked very hard in that team and the devs told me that - but the manager brought into question whether I was committed to it. There's a difference between being committed - and being willing to put up with totally unreasonable overtime expectations.
When I handed in my notice, HR and senior management wished me well and thanked me. My manager instead told me I was making a bad decision, that the sector I was going into had no growth, the increase in pay I would receive wouldn't be as great as I expected, etc. He'll pretty much use any trick in the book to manipulate. I didn't notice a thank you or a good luck, or even a hand shake from my manager as I left the office for the last time.