Even if you have that day-to-day focus on building and honing your product, every technical entrepreneur needs to face the challenge of knowing when to stop building and perfecting your product, and start selling it, even if building it is more fun than the business side.

Scope creep (or feature creep) is an insidious disease that kills more good startups than any other, especially high-tech ones, and yet most founders (who may be the cause) never even see it happening. This term refers to the penchant to add just one more feature to the product or service before its first delivery, just because you can, or you perceive the customer needs to have it. Other excuses often given are to occupy the market as soon as possible, or to collect feedback from customers and improve the product.

The instigators are all well-intentioned—executives talk to potential customers who "must have" a few more things, or the technical team prescribes...