Suppose you're working on a product that is time sensitive. In other words, if you don't start full time on it three months ago, you'll be too late to market. Also suppose that you see this opportunity while you're a student. Finally, consider that skilled programmers tend to be concentrated in high cost of living areas. In that case, you never had the opportunity to save up and you probably need to be where the potential cofounders and employees are, so you've no choice but to look for funding.