Or you could miss something, and end up having to debug from the start.
I also think that starting to thread simple code is much easier than threading at the end where u can miss something and might have to debug... for a while : )
And by the way, debuggers don't really work in multithreaded code. Nor do log/print statements.
The only realistic way to approach multithreading is from a purely mathematical/theoretical standpoint.
Multithreading has nothing to do with either Java or graphics. Nor "fun", for that matter.
Plus I am just doing this for fun to learn more about Java and graphics.