When going out to get a mortgage, the one thing people have as their top priority is to find the lowest rate of interest.
This is quite different from shopping for anything else where lowest price isn’t always the top priority. Buyers often also look for the quality of the product, its brand, reviews, etc.
The reason people think that way about mortgages is because a mortgage is a product where someone is lending you money. They’ll all lend you the same currency and the same amount. They think that as long as it’s the lowest rate, it’s the best choice.
That is a reasonable way to think about it. Except, the lowest rate of interest isn’t the metric to focus on. The lowest amount of interest is what should be. And therein comes the choice of mortgage product.