Even for a startup business, I can't advise anyone to borrow up all the money and start a business with it; it's too risky. The interest rate is attached to the amount on one side, and the risk of the new business, which will definitely incur losses, will mean a startup paying off monthly or weekly debt from the same business will only drag the business down more.

Cases where I can only advise anyone to take a loan to invest in Bitcoin or any other investment are if they already have an alternative option to repay the loan back and the investment they made will appear to be the second choice, which, if there is not enough profit to cover that loan and interest from the investment, your first choice will come into play and save you from the drama.