If you take SaaS, they are skewed towards buy, because their margin is ridiculously high. Better to hit the market now by using stable products than optimizing on spend.
The bigger you are and the more you can think about optimizing spend.
I think it is quite the opposite. Having worked in startups that were VC funded it seems they consider VC money free money and just spend a lot of it in infrastructure without the need to.
I know for a fact our bill was around 15-20k USD per month for running a webapp that could be ran in digital ocean 40 dollars/month.
For a lifestyle business without VC money to burn it makes all the difference.
Oh I've definitely seen that too. My example requires responsible (and smart) leadership. My thought is that optimizing costs engineering hours, which are much more expensive than paying for the service bills.
The bigger you are and the more you can think about optimizing spend.