~snip~
I'm not completely sure, but as far as I know, at least in recent history, it has never happened that the host of the World Cup did not pass the group and not advance to the knockout stage of the competition.
However, due to the quality of their team, Qatar does not deserve to play in this World Cup and I believe that they have a minimal chance to pass the group and reach the knockout stage of the competition.
If they aren't the hosts, we certainly wouldn't be watching them at this world championship, just as we haven't seen them at previous world championships either.
Yeah, it's a huge advantage to host the world cup. But the thing is that the previous world cups have been usually held in countries in which they have a strong team to begin with, such as Brazil, Spain, Germany, England, Uruguay, and so on.
This is probably the first time that it's going to be held in a relatively weaker country. Maybe Korea-Japan 2002 could be comparable up to a point, and even then they managed to go past the first stage, which has been their all time best performance for both Korea and Japan.
We'll have to see if the boost for playing local is enough for Qatar.