Small, fixed payments over time means you can afford to buy the other things you need in life without having to sacrifice a comfortable home atmosphere. Maybe you also need to make repairs on your roof to keep it up to code and avoid city fines? You have the money to make the repairs on your roof and get your plumbing or HVAC installation or repairs the same time. Or, if you want to think of yourself as a company, it would mean you can use the extra capital to purchase equipment, allowing you to grow and ultimately succeed.
You get more with financing. It's putting money in your pocket, and you paying that money back, little by little.