What is one main reason why a mortgage loan might be denied?

A mortgage loan might be denied primarily due to insufficient income or an unstable employment history. Lenders assess a borrower's ability to repay the loan based on their income and job stability. If a borrower does not have a reliable and sufficient income stream, it raises concerns about their capacity to make mortgage payments consistently. Likewise, an unstable employment history can signify risk to the lender as it may indicate potential financial instability in the future. This combination of factors is critical for lenders when evaluating the overall creditworthiness of an applicant.

In the context of the other options: excessive borrowing history might raise red flags but does not automatically lead to denial; having too many down payment options is generally not a factor that would lead to denial; and requesting pre-approval from multiple lenders is a common practice among borrowers to compare options and should not negatively impact a loan application.