It is critical to minimize the risk. Remember, you are taking somebody's money. Their main concern will be the payout and this is the likelihood of future income minus risk of losses. You probably spent some time thinking of future income (everybody does), now do your homework and work hard how to mitigate risks. With lower risks you can ask for more money for less stake in your budding enterprise.

With large amounts of money involved there will be more focus on risks involved and so it gets critical.