By the time Voldemort killed the Potters, his soul was so unstable that when his rebounding curse hits himself, his soul splits. However we learn that splitting one's soul too many times can be very dangerous (indeed Slughorn did not believe it possible to split it even twice), so does this mean that one did not actually need to destroy all of Voldemort's horcruxes in order to defeat him- they only needed to kill him until his soul was too 'diluted' for him to ever be able to form a body again?
The risk of creating a too many horcruxes could only occur if Voldemort actually try to make another one or if there are a situation like when Voldemort try to kill Harry, he is trying to make a horcrux and he is in a situation that without horcruxes he should die, so his soul breaks and he makes an accidental horcrux.
Also Voldemort makes another horcrux after losing his body.
So because Voldemort are not trying to make more horcrux his main soul have not risk of breaking and you need to destroy all horcrux to destroy Voldemort.