Pothole repairs should be performed while they are small before they grow too large for two important reasons.
1) Should a legal situation arise, a small pothole can undersandably be an oversight.
A small pothole that is allowed to grow large is hard to overlook and is perceived as neglect.
2) Repairing small potholes can be relatively inexpensive.
When potholes become large they can only be repaired by cutting them out which becomes much more expensive.