If they mean squat then why do all colleges and NFL teams want to know what they are? Believe me they mean alot, along with other test that measure speed and strength. They also will look at game film, and watch you play. But size, strength and times attract them.
And anyone 6'5", 260 and runs a 4.6 forty if they can tie their shoes they will make it big. Alot of highschool kids have 40 times that are blown way out. If a kid is this big and can play in highschool 4.8, 4.9 collegiate times will do.