What are the most common mistakes first-time entre­pre­neurs make?

Je ne vais pas parler de ma start-up, je ne ferai peut être un jour quand je serai passé à autre chose, mais de ma maigre expé­rience je seconde très très forte­ment les trois premiers points de la réponse la plus votée :

1. Keeping your idea secret.
This is one of the most stupid miscon­cep­tions about star­tup ideas (If I tell it to someone they’ll steal it and make millions of it) Reality is that every loser has a busi­ness idea with a poten­tial but most are not capable to execute it. And people who are able to execute ideas have plenty of their own. Of course, it’s the execu­tion not the idea – face­book came after friend­ster and myspace and google came after plenty of search engines.

2. Trying to build a product for everyone.
He who tries to please every­body, pleases nobody.

3. Lack of focus.
All entre­pre­neurs are cursed with having too many ideas that are too temp­ting not to be execu­ted. The point is to be able to put every­thing else aside and focus on one with best timing and most poten­tial. Jack Dorsey mentio­ned somw­here that he had his Twit­ter idea almost a decade before he star­ted it and put it in shelf – which is his way of clea­ring distrac­tions.