yeah I agree with the above statements about patience. for years right when I got an idea for a song, I would run and track it in an hour, always using the first take. sometimes I wouldn't even finish writing the song, just throw up a mic and hop on the drums and lay down a track. then bass-line...hit record before even fiddling with the music...I was just so happy to be recording my ideas... unfortunately when I go back and listen to my creations they are pretty horrible.
I still use a similar process, but I will at the least work out a part before I hit record, make sure the song is finished and I can play all the way through on guitar and vocals, and make sure I get a take that is maybe not perfect but at the least something I won't be embarassed with later on. back in high school anything I put onto tape sounded cool as shit... now its like keeping up with real studios...
oh yeah and air conditioning or ceiling fans turning on or off will put a guitar out of tune instantly.