I went into banking because I wanted to work for a PE firm or hedge fund. Unless you're well-connected or have a 3.8+ GPA, you need to do your analyst stint before any good buyside shop will hire you. I have no talents and no particularly strong entrepreneurial inclinations, but being a math/philosophy double-major, I liked thinking through problems. I like the idea of learning a company or situation inside out, taking a view on it, and strategizing how to execute on that view.
The pay is what attracts people who aren't generally interested, and what keeps people like me from just saying "fuck it" after 6 months. (The first year of being an analyst is probably the most miserable working experience anyone can go through...but by your third year, you can pretty much do the job on autopilot with no stress.)
None of this is to say the work isn't interesting -- in theory, it is. And when I was an analyst, it still felt cool to be part of a team of fewer than half a dozen bankers working on multi-billion dollar deals, especially compared to so many other jobs in the "Office Space" business world, like auditor or the ubiquitous "account executive." Now that I'm on the buy-side, I do sort of miss the pace and multiple deals of banking. (Private equity is *really* slow and process-oriented.) But in the end, I had absolutely no desire to be a client-facing marketer/agent/middleman, which is essentially a senior banker's primary function.