Most users are reluctant to try something new due to different reasons. It could either be ease of use or the fact that less people are using the same application as compared with another commercial application.
Then there’s the notion that something which is given FREE is not as good as it”s commercial counterpart!
Try OpenOffice! It’s open source. It’s free. It’s been around for 20 years! And more than 100 million people have downloaded it!