They are too afraid to show something imperfect to the world or are afraid that a competitor will steal their idea.
I would like to highlight another common sickness that is sort of the flip side to the Stealth Disease: the First Mover Paranoia – the idea that your product has to be absolutely unique or else you will fail. Any sign of a competitor doing the same thing or something similar will immediately kill the startup idea as the founders become morally defused.
You would have thought that examples such as Google (not the first search engine), Facebook (not the first social network) or Amazon (not the first online book store) would eradicate this disease, but no, it is still very much present and viral. I see the symptoms of it all the time – and yes, I have myself also been infected from time to time.
I wonder how many startups or potential startups fall victim to these two diseases. The First Mover Paranoia is extra vicious since it strikes so early. Often long before the execution of the startup idea is even started.
The cure for the First Mover Paranoia is to not view competitors as impassable roadblocks but as a verification that the idea actually works and has a market. That is in fact great news! Now the challenge becomes to find holes in the existing market (geographic, pricing, quality etc.) or to improve on what the competitor is doing.
Tough, but less tough than trying to bring something completely new to the market.