It depends!  I know, it seems like a cheap answer, but it is very true.  When it comes to ingrown nails, some are purely based on the shape of the toenail as it grows in.  In other instances, improper trimming of a nail, other deformities in the foot or certain shoes or even socks can cause issues to a nail that was never problematic before. 

Over time, it seems, our nails can change shape and curve more in some instances.  As with almost anything, it's important to look to your parents and see if they had similar issues as the shape of the nail can be genetically inherited.  The same is true for foot deformities (bunions) that cause the toes to be in closer proximity as they develop, which can aggravate nail borders.

In instances where a certain pair of shoes (usually with a narrower toe box) or even socks (usually compression stockings) cause the toes to crunch together, a nail which asymptomatically curved in before can become irritated.

Seeing your podiatrist can help you to get rid of the pain and typically we can determine over time if the issue will be recurrent or not and what treatment options have the best opportunity to help you!