There can be immediate issues with it or many other concerns as well like societal and cultural pressures and doing it before they can remember it gives 99% chance of no ill harms or memories and I think people just feel thats the better way to go. And its easier and much cheaper than having to deal with it later. Its like getting your wisdom teeth out. Its unnecessary for a lot of people but the majority still get them out just in case. Or moles on skin in case they develop something else. Its not the only one but its one the baby will never remember so unless its botched cuz you saw a shitty doctor and have bad health insurence, there will be no issues. Would you rather have a ticking bomb in your living room that youre not sure will ever go off or would ya rather take it out to a field and set it off in the middle of nowhere the moment you find it, and nobody knows it was there by time they would have come around and noticed it.