Lack of willpower, time, motivation.
I started studying programming and computer science in High School because I wanted to become a game developer. Never done that.
I recently got my degree and moved to another city to work as an embedded developer, but guess what, I don't really like this job.
But after 8h in the office, sitting in front of a screen, banging my head on the desk, I really don't want to come home and sit again in front of a computer. I want to work out, I want to cook, to bake bread.
And because of that I cannot really leave my job, I'm too afraid of interviews as there is nothing I'm actually good at (well, my sourdough bread and my pastries are quite good...) and I do not have the will to study.
About developing games... I'd love to work as a game dev. I read books about frameworks, try out engines, listen podcasts about game design. Problem is that there isn't really a market for it in Italy and I don't have the creativity to create something myself, but to find work or even just an internship you need to prove that you can publish something.
Sorry for the depressing answer :P
I understand the feeling. Sometimes it's easier to start with trying to improve the state of things during the work day, rather than burning energy you don't have at home.
To that end, this other article I wrote may help some:
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