Why does it take so long for Carbonite to backup my hard drive?

Episode 1130
Daryl fromDaryl wants to know how long Carbonite will take to backup his hard drive. Leo says to take 740kbps x 60 then divide by 10. 10 KB per minute. If he does the math, it takes quite a bit of time. Carbonite knows this and as such, Daryl can request to have a hard drive sent to him and then he can back up his system and sent it back.