Nice ideas,but he conflates 'must have' with 'wants'. I learned many years ago, working for 7-11, that selling what people wants is way better than selling necessities. People will nickel and dime you for every percent of margin on necessities, but will happily pay silly margins on wants.
I think I prefer "make something at least someone loves". That's more accurate because if 1 or more users love your product, you can get to 40% by getting rid of enough users who don't love it.
<i>Only when you hit that 40% number(or something in that range)</i><p>93.5% of bloggers make up bullshit statistics. 84.8% of people use statistics to obfuscate and distract people from the fact that they don't know wtf they're talking about.