1. It's a coin toss on whether you'd be assigned to either a great project or a horrible one. For me it was horrible both times (with the second one being worse). For my second project I got assigned to work on a notorious client with bad work-life reputation. Although I was in that project for a short time, it derailed my sense of self after an intense stress episode and developer's death in the project. I probably need to go to therapy because I have left this company and I'm still affected by it (unfortunately).
2. No bonus in sight after working for over 2 years >:(
3. Sometimes it can be very isolating when you're the only one assigned to work from a client site
4. Did not pay me my last allowance despite promising me it will be credited a month after my last day >:(