Because it's realistic. Banks in the 60s/70s handed out money like ice cream. Nowadays their not only legally obligated to ensure a portion has to be recovered in any outcome, but banks also learned their lessons and don't lend money 'for a good idea'. If Benzo would have planned his bookstore today, no way anyone on earth could have seriously considered it to be a billion dollars worth at any point.

My uncle is a employed in my countries largest bank specialised in loans and retiring next year having led the credit department. He would laugh at your proposal 'just provide a good plan and you'll get money'. Jeez, without some start capital or someone acting as surety you don't get shit even when you proof to foresee the future.

You're not in the wolf of wallstreet movie to have someone trash hundreds of thousands dollars to whatever shit you throw them at. You're a broke ass asking for money, without any experience in leading a successful business. One of hundreds who have a 'million dollar idea' everyday coming to the bank. You're not worth the risk, until you cover a part of the risk yourself, because there are plenty people with equally good und potential ideas who can cover their part.

But go ahead and try it yourself. Make a solid business plan and ask for the money. You seem to be sure it works that easy.