There is no such thing as default infrastructure if you care if your application works. Hiring "experts" later is really just hiring someone to do what the deve

There is no such thing as default infrastructure if you care if your application works. Hiring "experts" later is really just hiring someone to do what the developer should have done, and will probably have to ask the dev to do more work anyway. To an Ops person it's literally a black box. To "fine-tune" the infrastructure, they have to interrogate the developer, and learn only the bare minimum of whatever app stack the developer decided to use. The end result is literally black box reverse engineering, which is wasteful and leads to bad outcomes. Imagine being a fashion designer making clothes without ever seeing a human being put them on. There's fabric that covers skin, and there's arm holes and leg holes and buttons, so they are "feature-complete" clothes. But just because you pinned up a bunch of fabric on a dummy doesn't mean you know what a person looks like when they put it on and move around in it, or whether a person will want to wear them, or if they'll fall apart after a week. You have to know about different body shapes, how bodies move, evaluate their fit, adapt them to the wear and tear of the real world, and be interested in the outcome. You don't have to be a medical doctor, and you don't have to be an engineer, but you do need to know the absolute minimum of how those different domains interact with clothing.