Yep, honestly it is because like people have said, carbon will build up in the internals of the engine and will make performance sluggish if you baby it all the time. Carbon will still build up, no matter how you drive it, but revving it up evry so often will make the build-up slower than it would it you kept rpm's under say 4k.

Plus the engine was designed to high revs and high speeds. It's kinda like your body: you can live life normally every day and not push yourself @ all (like most American's do anyway) but when you go to run or if you suddenly wanna push yourself then it will be harder than if you do it regualrly. Exercise your car like you would (should) exercise your body. But @ the same time, you know your personal limits, so you also have to know you car's limits. I try not to rev my car to redline, my personal limit is 6k because I think that is peak hp anyway.