Lawyers, an army of lawyers. You don't want to get letters from Oracle, IBM, Intel and Co. because you infringed some of their EULAs. They may be invalid, but

Lawyers, an army of lawyers. You don't want to get letters from Oracle, IBM, Intel and Co. because you infringed some of their EULAs. They may be invalid, but it will be a very costly decade long court case. And the other part will pump thousands of times more money into it than you can afford, because when they loose they will loose a big income stream in the future.