The previous mistake is one of major consequences. And choosing the wrong platform is one of those consequences.
Much like the lack of knowledge to hire the right programmers, choosing the right platform for your service can be nerve wrecking. The wrong platform can completely destroy the purpose of your product. A number of companies failed to know this, and saw themselves waste away in the dot-com-bubble.
Think of your platform as the foundation of your house. Would you want to build your house with mediocre talent? I didn’t think so. There are some places where you just DON’T cut corners, and hiring the right programmers and choosing the right platform is one of them.
If you do end up hiring great programmers, you can easily avoid this mistake by letting them choose. However, if you still want to keep a close eye for yourself, you could always step into a top computer science department and peek into what they use for their researches.