As someone going into general surgery with possible aspirations for colorectal surgery, allow me to tell why I like the field.
1. Range of complexity in procedures from stapling hemorrhoids to technically demanding bowel resections and reconstructions. The latter is a fairly hot area in the realm of surgical innovation at the moment.
2. Patient population. The prevalence of colon CA is expected to increase with the aging population. Until the last decade or so, IBD patients have had little expertise support from the surgery side and there is a need for such support. These groups constitute the remainder of the common patients you see other than the routine hemorrhoids, anal fissures, etc. And while you may see many patients with more routine complaints, they tend to be very appreciative when they leave your office.
3. Opportunity to perform other procedures. With the ability to perform lower GI endoscopy, you can offer patients a wider spectrum of surgical care than what most general surgeons do (not all, I understand). Yes, you have to toe the line with GI, but at least at my institution the GIs are too busy to scope everyone anyway.
Other points about pay and work schedule may be relevant, but at this early stage when I ponder my ultimate career path, I prefer to think about what will excite me for years to come (i.e., the "Monday morning test"). I would rather work a few more hours a week and earn less income than be unhappy or bored. At least my wife would rather have me come home in a better mood after a long day than the alternative.