The first release of a feature is often just a foundation for the iteration that is going to be required for the feature to be successful. Just sticking up something like a link to sign up for an alert isn’t sufficient. You’ve got to merchandise it, track how it’s being used, improve the parts that aren’t working until it hums.
Adopting the mindset that you are going to need to invest in features to make sure they disappear and just work helps avoid the disappointment that can result if you just expect it to catch fire the instant you release it.
Another benefit of continuous improvement is that people who do adopt the feature early find themselves enjoying its evolution.¬†Ideally you would use their feedback to make it better, so they also feel like you’re being responsive and that your product is alive.
Things do explode out of the gate from time to time, but it’s the exception, not the rule. Focusing on making a feature better after its initial release requires having the discipline to work on the next new, shiny piece of functionality.