Everyone can 'have a go'.
If the score was way to high for them to reach how would they expect to be the new champion?
What's the point in being the champion when you know that you're only the champion because the people who are normally better than you haven't had the chance to compete yet. That's just sad glory if you ask me.
Don't let big scores dishearten you, they are not impossible to beat (except for Space Ace ).
I'm not against resetting the scores now and then but not every month... Once a year sounds much better.