1. Product Owners expertise. POs usually don't understand how their products actually work. That's why they always ask the developers, "When the task will be finished?" It's okay to ask this from time to time, but not on a daily basis. One should always be ready to defend their position, explaining why the estimates are "so pessimistic" (even if they are actually optimistic). This can become tedious after some time, given that there are a lot of other responsibilities, and it does not improve the developer's long-term productivity.
2. The work culture is quite toxic. Everyone has a lot on their plate, which complicates interactions between teams. It's quite common to be blocked for several days, or even longer, by approvals, answers, etc., from someone else.
3. Promotions. The promotion mainly depends on the opinions of line manager (LM) and functional manager (FM). The FM might be from a different team, have many other responsibilities, and not have time to properly assess one's work. The promotion can be deserved and not granted just because the FM "doesn't feel" that it is deserved.
4. Team structure and the lack of people. There are no Team Leads. Being the only Backend/iOS/Android/Web developer on the team is also possible. If that's the case, be prepared to receive tons of daily DMs from POs, developers, operations managers, etc., with different requests/questions. Having to switch between different tasks is also very common: it makes it harder to concentrate on important work and deliver good results. It also leads to overtime (most employees do overtime).
5. Focus on KPIs that lead to absurd decisions. For example, there can be a very important task that affects many customers, but it won't be addressed because there is another minor (not always easy-to-fix) bug that affects the KPI.
6. Relocation. The company exploited the vulnerable position of people who had to relocate because of the war and didn't offer good salaries to some of them. The relocation process was not as fast as it could have been, but the global mobility team kept saying that "The safety and well-being of our employees is our top priority," which kind of became a local meme.