With rates having beat historically low rates over and over lately, you might ask what is more important than getting the lowest mortgage interest rate? Actually closing with that interest rate and what you were promised from the start. Most mortgage lenders are backed up and when you're shopping for the lowest rate or the best mortgage terms, take into consideration that lender's capacity. This can determine if you'll actually make it to the finish line with the same terms, or at all. Research the lender on multiple platforms and see what people are saying about the mortgage lender, bank, or broker.
If you get quoted a 1.75% rate, it's completely irrelevant if you never close (many end up paying for 2-4 lock extensions) or if your locked in terms expire. I can't tell you how many people I've talked with who are shopping for a refinance but they've started elsewhere and are starting over again 30-90 days later since they can't get a hold of anyone or are being asked for the same documents over and over. RATE DOESN'T MATTER IF YOU NEVER GET IT - read that again. If you can actually close on a real-market rate of 2.375% and get what you were promised, it's much more beneficial than thinking you're getting a 1.75% and never closing. Especially in the mortgage industry this statement always holds true, "IF IT SOUNDS TOO GOOD TO BE TRUE, IT NORMALLY ALWAYS IS."