Archaeology student here, it depends on the figurine/location/date. With later periods we can deduct ritualistic purposes as they are found en masse as offerings at temples for example. Figurines also served as toys, sometimes found in settlements but more so in children graves they are prominent. Now with prehistoric times I assume you mean the well known Venus figurines? Honestly we don’t know their purpose, there isn’t enough evidence and they haven’t been studied enough yet to make a conclusion. There are hypothesis out there, but no real answer yet. The “may be ritualistic” is often quickly thrown around when they don’t know what else it could be yet, sometimes too quickly.