YC is an investment company. They certainly do help their investments to do well, but I don't think they would keep from funding a similar company if they think it will increase their potential return.
After all, they expect a good deal of their companies to fail. If they didn't fail because of the idea then doubling up through a similar company is a good way to increase their odds. They might not fund competitors in the same cycle though.
After all, they expect a good deal of their companies to fail. If they didn't fail because of the idea then doubling up through a similar company is a good way to increase their odds. They might not fund competitors in the same cycle though.