According to a recent study by the World Economic Foundation, these 30 countries are the most approving of the tourism industry as well as the most welcoming to foreign visitors. The study ranks countries based on three major component rankings: Tourist Service Infrastructure, International Openness, and Prioritization of Travel & Tourism.
That means that this "welcomeness ranking" has more to say regarding government policies than how pleasant local residents are to foreign visitors. So really, it's a reflection of political and business leaders and not everyday people.
What that means is that, in general, these nation's governmental policies would rather you visit their country than stay at home. One important caveat is that countries weren't ranked at all if they didn't respond or provide adequate documentation of the survey. So that means that some truly welcoming places may have been left out...simply because they didn't respond in time or provide enough information to a third party. And they might not have done so because they were too busy making sure their tourists were having a good time! Who cares about a survey when you're addressing the concerns of real people?!