One of the best things about Magento is that it is extensible – anyone can create a Magento extension and share it or sell it to other Magento users. The ease with which you can create extensions has some downsides, however. There are a lot of extensions on the market.

Discoverability

One of the biggest problems with online app/extension stores – such as Magento Connect – is discoverability. When there are thousands of extensions to choose from, why should a user pick your extension over another one that is free, was made by more well-known web developers, or has been around longer.
You can drive attention to your profile through marketing – promoting your extension via social media, reaching out to web design bloggers, and taking out ads on popular web design sites. However, all this does is drive eyeballs to your profile. There’s more to building a user base than simply getting people to look at your extension.

The Issue of Trust

Few web developers are willing to run unknown code on a production website. To persuade people to install your plugin, you need to get them to trust you. One way to do this is to fill out your Magento Connect profile properly.
Take the time to upload a logo, fill out detailed contact information for your business, and link to your support page. In addition, create a professional looking logo for your extension, and fill out the details page properly. If it looks like you’ve put effort into your profile, people are more likely to believe that you’ve put effort into your extension too.
Encourage people to rate your extension after they’ve used it, and respond to comments and questions so that people know you care about your users. In a saturated market, a simple, working product produced by a developer that cares is far more likely to do well than a sophisticated extension from an unknown, unresponsive developer.