I disagree about the sunshine and friend. Getting good outdoors shots in bright light isn't easy. Seeing photographers at work in such an environment there are always assistants with reflectors and scrims.
Well it worked for me without any assistants or reflectors. I had over 400 images on IS before I got around to buying some lights. Back then we were only averaging about 20c per sale so I wasn't confident that it was worth splashing out the money for them. Technical standards were lower then but even so the majority of my outdoor shots would still pass inspection today.
I didn't particularly like using the lights either (it didn't help that they were cheap rubbish off eBay) so it probably took another year or two and the frustration of weeks of lousy weather before I bothered to learn how to use them properly. Shooting outdoors is still my preference for pure enjoyment __ the studio stuff probably pays better and is more predictable but it is purely 'work'. If I wanted to teach a complete novice about stock photography I would most definitely start them outdoors before progressing to using studio lights.