As KristaK say, some stats will converge faster, because they happen every hand, while others might take tousinds of hands to become meaningfull. If in dought its always a good idea to look at the number of times, something has happened, and if its only one or two, then the stat will be completely meaningless. Like someone folding to flop C-bet 100% of the time, but its two out of two opportunities. Thats not a green light for you to go ahead and C-bet like crazy.
Also stats, that are way out of line, will be meaningfull earlier. If someone has stats like VPIP 91 / PFR 9 after 11 hands, then this player is with 100% certainty a huge whale, and you can start making adjustments already. Maybe his numbers will eventually drop to for instance VPIP 58 / PFR 12, but there is no chance, that this is a good player with reasonable preflop hand selection. Whereas if someone has stats like VPIP 0 / PFR 0 after 11 hands, they might just have been card dead, and you can not yet conclude, that this player is a nit. To draw that conclusion you probably need to have at least 50 or even better 100 hands.