I have friends who collect and restore classic cars. They spend all their time working on the cars, but never drive them except to take them to car shows... which is a waste of a good car as far as I'm concerned.
Some people do the same with bikes. Although I admire the effort and dedication that goes into restoring a classic bike to "like new or better" condition, I think it's a shame when we turn an great riding machine into an pristine, unusable collectors item.
I think bikes are made to be ridden. I believe it's better to get an old bike into good, stable working order... the ride the h*ll out of it.
Of course, there are exceptions: Bikes of personal sentimental value, and bikes of historical significance... such as a bike used to win the TdF, etc.
Perfectionists take note: This is my personal philosophy. Like I said, I admire how you restore a bike down to the last little detail. It's just not the way I would do it.