When you've first started out, you haven't generated a lot of value, even if you've got a plan, a great team, and an MVP. Your company just isn't worth very much at this point, which is why early-stage (angel) investors get large amounts of equity for very small amounts of money.
By raising a large amount of money at a low valuation, you limit your options for future financing, as you can only offer a smaller slice of the pie to future investors, and have to do it at a higher valuation in order to keep your initial investment team happy.
By raising a large amount of money at a low valuation, you limit your options for future financing, as you can only offer a smaller slice of the pie to future investors, and have to do it at a higher valuation in order to keep your initial investment team happy.