Well, I guess there are a variety of reasons for that. I mean, maybe you just didn't... gel with those particular courses or professors responsible for teaching

Well, I guess there are a variety of reasons for that. I mean, maybe you just didn't... gel with those particular courses or professors responsible for teaching your computer science at that particular university. That wouldn't necessarily mean you were bad at the subject. Just that you didn't learn well in that particular environment. Alternatively, if you've got ADD and find it hard to maintain focus, maybe you just didn't care to work as hard in college as you then did in the internships and roles you took on afterwards. We've all had companies and organisations where we've been good/bad culture fits (like Amazon as mentioned in your post). Perhaps your college/classes were a poor fit as well. Alternatively, it could simply be an age or maturity thing. I'm sure many people here would do much better at school or university if they returned today, simply because they'd take it a bit more seriously and have more years of experience under their belt.