tl;dr<p>Mistake 1. They have collected beta invitation email addresses but did not send any emails until the launch. Some users forgot about the product when they received the invitation 3-6 months later.<p>Mistake 2. They used spreadsheets to track user cohorts and that was too time consuming.<p>Mistake 3. They focused too much on features instead of benefits.<p>Mistake 4. They weren't able to find ways to get exposure from blogs.
If you are going to collect emails to promote your app launch, send out a useful email to your list every week or two. Your open rates and click through rates will be MUCH higher on launch.<p>Also, if you are "too busy" to communicate with your customers before launch, you probably won't have many customers after launch.
#5: Writing large blocks of text using a tiny gray sans serif font and expecting people to read it.<p>Sorry, my eyes just won't hack that this early in the morning.
Beta invitation and getting subscribers pre-launch is in many cases a flawed strategy. It is really, <i>really</i> hard for an unknown startup (amongst hundreds of other unknown startups) to stay 'top of mind' for more than a week or so.<p>For the beta and pre-launch startups I sign up for, I remember only half by the time I can register and use the service. I register for about 5% of those I still recognise. For the rest, I simply don't care any more.<p>Rethink the pre-launch and onboarding strategy. Just because others say you should doesn't mean it will work for you. THINK FOR YOURSELF.