Good list! I'd add 16) Acting on tactics, rather than strategy 17) Building before validating 18) No product / market fit 19) No founder / industry fit 20) Yo

Good list! I'd add 16) Acting on tactics, rather than strategy 17) Building before validating 18) No product / market fit 19) No founder / industry fit 20) You can't build a sales team 21) Building when you should be selling 22) Not talking to customers, enough 23) Not understanding your industries cost structure 24) Not understanding the emotional reason people should use your product