[dpeck]

| simply take my idea and with their infinite balance sheets build it themselves

If large businesses were actually able to do this then the vast majority of startups would never exist. These days many startups are really just speculative r&d for big co's that like to spend capex for a (mostly) known commodity vs opex that may never amount to anything.

You probably wont make them a customer, but the chances of big co managing to take your idea, implement it, and put it out into the market to compete with you is vanishingly small.