Why compete in the biggest pool when you can dominate a smaller one?
In Europe, for example, you have a much less homogenous market. A French retailer/business may be popular in France, but has a lot of friction going to another market. Not so much in the US.
So large, homogenous, wealthy culture that, if you can address a problem for, creates a financial foundation, and makes your app exist in at least a cultural context somewhat portable to other markets outside the US.
Who cares if you’re the king of some country in Africa. Manhattan has more money to slush around on apps than the entire continent combined and that’s literally just one area of one city in one state in the USA.
You keep mentioning Brazil in your comments, but as a founder I'd rather not have to keep track of the various government officials I have to bribe in order to be compliant, and even then, not be completely sure.
I hate lawyers and I hate governmental red tape, but at least in the US it's consistent, and the rules are laid out for you ahead of time. Finding out three months after launch that you have to buy Chico's cousin a hooker in order to get your business license renewed is suboptimal.
But if you're selling there, you can still manage to avoid a lot of the red tape, bureaucracy, etc. You can be a c-corp and sell there. I'm sure a lot of the US companies that sell there don't have to engage in all that, so why not focus on that market?
You need to clarify this with real examples. Which Markets ? The reason everyone wants to be in US Market is because of the size, adoption, maturity of consumers (willingness to spend) and many other reasons. Yes there may be markets where it may be easier to replicate but they have limits and ultimately you want a piece of the US Market.
Sure they have limits but why start in the US? What makes it great is what makes it super competitive.
I think you can achieve "scale" in markets like Brazil which aren't as attractive but still have +200M people if you build the right thing.
And the right thing can be simple and something that has worked in markets like the US before.
The natural lifecycle of online communication services is that they burn out and get replaced rather rapidly. It seems as soon as one gets enough users to reach critical mass it is very hard to peel people away but inevitably when that happens the service stops investing in reliability, never mind new features, so maybe 5-10 years or so later people are saying: “I know you’re skeptical about trying new apps but this one really works, it is like Skype was 10 years ago…”
To look at Twitter in particular there are a lot of people who can’t seem to quit using it even when they know better.
US is oversaturated with products, solutions, competitors, etc...
I’m currently building a product for the UK market, because like you say there is less competition. I won’t argue against that, but the fact remains that if my product were a success in the US market it would make more profit.