"In addition, the issuance of shares of common stock creates three potential problems. First, the founders risk substantial dilution because it is often difficult for the founders and the investors to agree on a valuation for the startup and, accordingly, to agree on the percentage ownership the investor will receive."<p>Isn't determining the cap of the convertible note equivalent to negotiating the valuation when issuing stocks? The dilution won't occur until the conversion, but it will occur eventually and at the ratio that was determined at the time of issuing the note. I think the above applies to uncapped notes, but I don't believe those are very common.