There are many factors that go into assessing a borrower and usually a multitude of reasons are taken into consideration instead of one single main factor and each lender will have their own credit system just like when deciding to buy a house or a car, there are many things you would balance into consideration such as location, the amenities around and not just the pricing.
These factors may change from time to time for reasons such as a change in their targeted demographic, diversification to ensure they are not overly exposed to a certain industry. It is not a hard and fast rule & any reason provided can serve as a guide. In general, a lender would look at the following, which if improved upon in the near future, may change their consideration:
Credit and repayment history.
Cash flow history and projections for the business.
Collateral available to secure the loan.
Character (credit score, litigation).