- I am highly debt-averse. I grew up financially insecure, and I feel better knowing that my house and my car are MINE. Yes, this is an opinion, but all the math in the world won't make me sleep better at night. Knowing that every brick and all four tires belong to me, me, me removes a significant amount of stress from my life.
- Buying a car outright, you're more focused on the total amount ... whereas, if you make payments, it's easier to fall into the "it's only a few more dollars each month" mindset, which makes it easier to say, "I think I will get the heated seats or fancy stereo or whatever".
- It's easier to buy a car outright rather than financing it. No financing paperwork, no waiting for credit checks, no making payments each month. Just less hassle. When you're paying cash, you feel more in control of the sale -- you're not waiting for them to check credit (even though you KNOW you're perfectly good) or anything else; whereas, if you finance, it feels like you're asking their approval /permission to spend your own money.
- No possibility of missing a payment or having the bank fail to credit a payment. It'd only take once for this to wipe out any potential savings.
- I personally wouldn't buy a car that would deplete my on-hand cash to the point that it would matter in terms of interest earned.