Sure, I can code an app in my bedroom after work in a year, but what about all of the prerequisite customer development (ie talking to your target market and making sure your app solves real problems and has reasonable usability etc)? What about marketing and sales? Support? Accounting? Hiring people (fulltime, part time or contract) who have skills you do not have yourself? Legal advice?
There’s a lot more to running a business than the coding part and these things take time (and sometimes money). The 50k to 1M estimate is greatly inflated by those other concerns.
Plus, while I can save, say, 250k, that would take me years and then I wouldn’t want to risk all of my savings into one gamble (I obviously wouldn’t take the startup risk if I didn’t believe in what I was building but even if I thought it was a sure thing, I’ve founded two failed startups already, it would be prudent to allow for a high chance of failure even if certain that the business is perfect)
Also, let’s assume everything above is irrelevant and I decide to save up my earnings and go all in on a startup. Let’s say I put 250k in and it takes me five years to save (in reality, I don’t think I could do it in that time, but let’s inagine I can). Let’s also assume that I do as much as work during those five years as possible so that when I have the money, I’m ready to launch. That means that five years from now, I can launch my startup, spend the money on whatever is needed that I couldn’t do previously and hopefully not lose it all (assuming the market still exists, 5 years is a long time in tech land). OR I could give up 5–40% of the company, put up with some hassle of having an investor and launch in a year (assuming development takes a year regardless). That gives me four years to make sure that the remaining % is worth more than -250k (which is where I’m at with the first scenario after that time). The investment route seems like a no brainier to me in this case.
Obviously it is possible to bootstrap a company and it should be the preferred route imho if you can pull it off. For many people, this isn’t an option though and that’s why VCs are becessary.