I've been thinking about this for quite a while, since my guitar teacher is a "do whatever you want, I don't care" kind of guy I have a fleeling that I have a few bad habits with my playing that I'd like to get rid of. And I don't think I am the only one with some bad habits who doesn't know about them. So what are the most usual bad habits for guitarists without anyone to point out the bad habits? Thanks in advance, and I'm sure I'm not the only one who's been thinking about this

I do the thumb wrap around thing and i find it more comfortable to what are the benefits of not doing it?

These are things that You have to make a point to do.
1. Not Practicing-This ones key always practice, when i first started i never practiced but still wanted to be a guitar god like kris, gabriel,pavel walliman etc.

2. Using all 4 of your fingers on your left hand when neccessary-A must

3. Practice on a clean setting when learning new riffs, techniques, solos, songs, jams etc etc. And once mastered play with a little disortion . The only reason im saying this is because distorion is like a mistake hider. And you would probably rather pick up your mistakes then hide them . No ?

4. Dont pick your calcuses on your fingers ! They are there for a reason !
hope that helped. - John

Much greater mobility, reach, and accuracy with your fretting hand, once you're used to 'proper' thumb position.
STANDARD DISCLAIMER:
IMHO and generally speaking, of course.

Agree. Wrap you thumb and place your fingers on the fretboard as spread as you can. Now place your thumb properly, and do the same. Yes, most commercially successful electric guitarists wrap the thumb. Hendrix was as bad as you get about that. However good your playing may be, it would be better without this habit. Ask any classical guitarist about this. But it is hard to break once you have it. You can get to be a great guitarist, and at that point in order to break it, you have to accept being a sort of crappy guitarist for awhile. So people generally won't break the habit once it is really ingrained.

There can be times where you will want to wrap your thumb, but it should be for a special reason, not your normal manner of playing.

I was going to say "not using the pinkie finger" as another bad habit. But someone else said that. You can do more with your pinkie than most people think. Kris has mentioned that, I believe Pavel also.

I believe those are the two really bad habits to stay away from in your formative years.