Are you still using Selenium in 2017?
A few years ago, developers would just write some Selenium Tests with Java or Python and run those tests on a headless browser.
It may seem crazy, but that was the approach for Automated Testing back then. To do such a thing in today’s world would be extremely risky, sloppy and irresponsible. Especially because Selenium is critically outdated.
Your automated tests need to run on a whole bunch of browsers, operating systems, platforms and mobile devices. You might be able to achieve this by using Selenium Grid, but it would be quite expensive, time-consuming and unstable.
If you haven’t heard of platforms like Endtest, that’s the reason why you’re not releasing with confidence.