Especially if you're a small company, engineering time (really any employee time) is _insanely valuable_.
This is true, but it is balanced by the fact that uncertainty can be insanely expensive. And diving into complicated cloud infrastructure with a small business, if you're not already an expert on it, is a very uncertain endeavour in terms of whether you'll get everything set up right (and not find out otherwise at 3am when it turns out your redundancy wasn't, for example) and what everything will cost. By the time you have either become an expert yourself or hired someone who already is, your costs have already increased significantly too, for exactly the reason you've just stated yourself.
This is true, but it is balanced by the fact that uncertainty can be insanely expensive. And diving into complicated cloud infrastructure with a small business, if you're not already an expert on it, is a very uncertain endeavour in terms of whether you'll get everything set up right (and not find out otherwise at 3am when it turns out your redundancy wasn't, for example) and what everything will cost. By the time you have either become an expert yourself or hired someone who already is, your costs have already increased significantly too, for exactly the reason you've just stated yourself.