To hegemony and all the others who answered the topic with "no", good form is not inevitable, please realize the question was not whether GREAT FORM is inevitable, merely good form. And even then, admittedly, graduation from weak form to good form depends mostly on exposure to good form in others and a desire to get better.
Look at the lifers (long time players) who fail to get to a 900 handicap rating. I'm guessing 900 is an attainable goal for any guy under 50 with a modicum of athletic skills or decent motivation, is this fair? Anyway most of them play with the same group of buddies week after week, year after year, who are also lifers and also not very good.
I play in a lot of local leagues and watch the progress of many new players. Because my leagues also attract many established players in the Pro to Am 1 range, newbies get to see a lot of good shots and good techniques. This leads to good form through mere mimicking of what they see. I actually think it is difficult for a player to regularly play with good players and not become good himself. Or herself, of course.