What are good reasons not to create a for-profit AI applied deep-learning startup starting with a team who are concerned about AI risk?

Gaining expertise, reputation and network are valuable, especially if you're concerned about AI risk. Revenue will be higher in worlds where AI advances more quickly, which is altruistically useful. The climate is very favourable for this kind of company to be funded presently, both by angels/VCs and by grant-funding such as FLI's. This would have a chance of growing much faster than MIRI, due to the for-profit company structure, and could be aborted if it was excessively speeding-up AI progress, or was otherwise net harmful.

Why should or shouldn't this be done?