I'm currently coursing a computer science graduation at a Federal University in Brazil. I work on a startup as a trainee in web development. My boss is a really great person, but there are many reasons that I want to leave the company:
First of all, I work exclusively with other trainee, that unfortunately, is terrible at work. He constantly loses deadlines and he always wants to decide what kind of solution we will take. We also are trying to apply the SCRUM method, but eventually he does not appears on our sprints and does not justify his absence.
Other problem with this guy is that he always want to choose the tool that we want to use like Rails, Angular, Trello. I really don't have a problem with this, because I think if I don't know how the tool works, I will try to learn by myself, and if I fail, at least, I hope that the person that choosed the tool have a minimal amount of knowledge about it. But is that not the case. When we start to work with Rails, by decision of this trainee, I was facing some problems and he usually didn't know how to solve then too.
Yet I have said that my boss is a great person, he has his flaws too. As I said, my partner usually loses deadlines, so my boss wants when I finish my part, he wants I implement the tasks of the other trainee!
Finally, I recently applied to a test on other company (that will pay me more by same amount of time) and they said that the probability of I being approve is big.
OBS: I will only leave my company if some other grant me a new job.