Essentially, these clauses give home buyers a way to back out of the deal if they are unable to secure a mortgage loan to complete the purchase. (homebuyinginstitute.com)
The contract states you can back out of the deal for any reason during those 10 - 15 days. (biggerpockets.com)
A date prior to closing where you must have a firm commitment to lend or be able to back out of the deal with no recourse. (merrimackvalleymarealestate.com)