How often is it repeated on HN that ideas are great and important, but implementation is the key? Why is it a problem if there is more than one version of the s

How often is it repeated on HN that ideas are great and important, but implementation is the key? Why is it a problem if there is more than one version of the same concept? What if some people just aren't creative but are great when it comes to execution? More important, who are you to complain about what other people are making?