The problem isn't to find problem for which you can start a business. The problem is to find a problem for which you can start an automated business. That's much harder.

Every business can be automated. Just find good people to run it for you.

That's not the spirit of the 4HWW. The idea is to make a product that requires not much improvement, and people just buy it from your website, so essentially your 4 hours are spent doing accounting and basic customer support. You might have a part time guy to do server maintenance but that's about it. So essentially most of your revenue is profit for yourself, and you can run a "small" business with revenue in the 50-100K range.

If you start hiring full time workers, then your business has to scale a lot. Like revenue has to go to 500-1M range so you have enough to pay full time workers as well as money for yourself. That's just a completely different beast.

500-1M USD? If you hire full-time US workers then that's probably the case.

For me I hired a few remote part-timers around the world. So it costs me an order of magnitude less. And they're all awesome, so I barely have to lift a finger.