The huge difference between interest and paying customers (and a validated product) presented in the “get fit” analogy.
I already spoke it on my postmortem startup lessons after 2 years, 300 users and 0 revenue, but I want to expand on why collecting emails is useful, but does not validate your product idea or niche market.
If I ask “would you like to be fitter and lose some weight?”, most people would say “yes, I would like that”. Then I say “Ok, give me your email address if you are interested, I promise I won’t spam”. They give me their email address, probably the one they use for spam.
Finally, I tell them “alright, to get fitter and lose weight, all you have to do is exercise 30 minutes every day and eat less unhealthy crap”.
Suddenly 99% of the people who “wanted to get fit and lose weight” are not interested anymore. Why not? Don’t they want to be fit? They just told me! They do, but they don’t want it badly enough to put the effort necessary to be fit.
Startup landing pages are the same thing:
Startup: Are you interested in this? So give me your email.
Startup: Great, now give me money and put time in it.
Prospect: Hmm… I have so much on my plate right now. I will pass, thanks.
Bottom-line: capturing leads is useful, but it is not even close to validating a product. The ultimate product validation is cash changing hands. For this to happen, the prospect’s pain needs to be bigger than the resources (money, time, etc) invested to get the painkiller.