Because the buyer may not discover a problem - until he’s the seller.
This is yet another reason why nobody should buy or sell real estate without having an attorney. All of the documents are written by lawyers, and the bank’s lawyer is present at the close, most “homebuyers” go in naked and haven’t a clue what half of it means, and mistaken about the other half.
“Title insurance” protects the lender, not the buyer. They make the buyer pay for it (along with everything else).
question, you are talking about "Title Insurance" which is an insurance policy, a title SEARCH is performed to assure you that there is no outstanding lean/loan or claim of other ownership, NOT insurance...
if a title search company does a search and gives you a clean bill of sale and it turns out to be WRONG, you can SUE the title search company