In that case, it was a bad deal, but it was the only deal, and was something we likely should have done. I didn't block it but did ask so many questions they tabled the deal. Bad deals are like that--they don't do the job of convincing everyone it should get done, and then they languish.
With deals, there's negative dilution and positive dilution. Negative dilution is when you give up a percentage of ownership and get nothing (or worse) for it. Positive dilution is when you give up a percentage and get more than what you gave for it. Employee options, new capital, partnerships, new equipment--every investment is about positive or negative dilution.
When something costs you nothing but brings the possibility of revenue, new markets, brand awareness, and opportunities, you're nuts to say no. When it costs you nothing, you say yes. But many, many entrepreneurs say no for one reason or another--scarcity mentality, control issues, fear.
And many amazing technologies go unknown and unused, without benefit to the world or to their inventors. I've heard about this, read about it, experienced it with Mission Research, and just recently witnessed something in freefall that has no reason to fail and every reason to succeed. Owning 100% of nothing gets you nowhere. Sometimes you need to give to get--a cliche, but meaningful.
But great ideas need at least mediocre execution to thrive. My dad gave all of his kids a framed piece with a quote from Calvin Coolidge--perhaps his only great contribution to the world:
Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. The slogan 'Press On' has solved and always will solve the problems of the human race.
Tenacity, persistence--yes. But openness and trust make a huge difference too. The 100% of Nothing argument is a good one, but don't ever let someone influence your choices using the fear of losing everything.
You can lose everything and bounce back--that's why entrepreneurs are so admired. We lose everything, we fight back, we win against the odds, and then some of us lose it again, just to rediscover that tenacity and fight back to win another day. So don't give up, and don't give in to the fears.