How a Sacco actually decides what you can borrow
A Sacco applies two tests and takes the lower answer. The first is your deposits multiplied by a factor the Sacco sets, less anything you already owe it, because an existing loan is already drawn against the same deposits. The second is affordability: whether the monthly repayment fits inside the share of your pay that you and your employer can commit to deductions. Most members only ever hear about the first test, and are then surprised when the second one binds.
This is the structural difference from a bank. A bank generally lends against income. A Sacco generally lends against deposits, which is why someone earning modestly with four years of consistent contributions can often borrow more than someone earning well who joined last quarter. Time in the Sacco is the asset, and there is no way to compress it.