This may be a complete newbie and peculiar question but just curious, what changes take place in the lip as one practices?

When I first blew the trumpet a week ago, the only sounds were mostly airy hissing sounds with a very distorted, raspy note once in a while. With daily practice, the notes started to come more often and less of the airy hissing.

At first, I could not do lip buzzing at all, seemed like the lip was too sluggish like a piece of clay but now I can lip buzz fairly well.

It's been a week now, learning as much as possible, doing exercises like the pencil thing and practicing long, low notes. The note tone quality has improved greatly, no more raspy and it actually sounds like a trumpet now, very encouraging.