[mcswell]

Kinda hard to see it growing on your back. (As a kid I got sunburned--mostly on my back--several times, and am therefore at risk.)

Also, as one (or at least I) gets older, you get a lot of other skin "things": "age" spots, basal and squamous cell carcinomas (kinds of skin cancer, but not as concerning as melanoma), actinic keratosis (non-cancerous), keloids, freckles, and on and on. There are lots of guides on-line to distinguishing among them, but I've seen spots on myself that looked concerning, only to have my dermatologist (old and very experienced) tell me they're nothing to worry about--and sure enough, ten years later nothing has happened.

And on the other hand he found and removed a squamous cell carcinoma that I couldn't even see (yes, even with my glasses on!), confirmed by biopsy.

So I would never trust myself to detect a melanoma, or even a basal or squamous cell carcinoma. I visit the dermatologist once or twice a year, and he always reminds me to stay out of the sun (because cancer) and out of the full moon (because werewolf).