i tell every entrepreneur the same thing: find the one thing that you can be the best at and do that one thing to the exclusion of all other things. the biggest mistake entrepreneurs make is that they end up [taking on] a lot of different tasks, rather than just saying, ‘we’re going to be the best at this. all we’re going to do is this.’ when i am in product-development mode, i’m notorious for not answering calls or e-mails. i’m not going to be distracted by taking meetings. i’m focused on getting my one thing done.

- jason goldberg, cofounder and ceo of fab aka betashop [emphasis mine]