1. The nail will cover the wound and the wound will start to hurt more, and might not heal for a longer period of time.
2. The nail could just grow in an uncomfortable way (like I said, into your toe), and then you'd have a lot more trouble dealing with it later.
That's just from experience though. Trust me, you don't want to sit in the bathtub with a needle under your flimsy new toenail trying to take out a scab because it felt like a splinter under your nail that you couldn't reach.
GL HF DD.