An old employer or personnel agency from the past would like to tell you about a great job.
You've moved and your alma mater would like to find you in order to invite you to a class reunion.
An old friend is trying to find you.
You were part of an adoption program years ago, your siblings are trying to find you.
A distant relative died and left you some money, they want to find you to give you the money.
An old flame from high school days would like to look you up an see you again.
You may be able to help a distant relative fill some blanks in their family genealogy.
You may be a run-away or estranged, missing from your family and one of them is trying to find you.
etc., etc., etc., etc.