The recommended read on the homepage doesn't begin show how much of a horrible idea it is to have the World Championships in Daegu. And this is coming from a native of Korea.
-Daegu is probably the hottest city on the Korean peninsula, average of very high 80s during the late summer. Add humidity to that and you don't have a very enjoyable track and field experience.
-A monsoon season strikes Korea in the summer. Recently it has become hard for meteorologists in Korea to predict when these come. This year the torrential rains flooded Seoul pretty badly in July and caused a lot of damage.
-As mentioned, Korea has no athletics tradition... I would say the national records are comparable to top times in any given year in high school track in the United States---both distance and sprints. Some events like the 100, not even. I recently came across a newspaper article declaring a 1:56 fifteen year old 800 runner as the "future of Korean track and field."
We do have a bit of a marathoning history (Gold in 1936 Berlin, 1992 Barcelona, last non-African to win Boston) but as of late things aren't looking up.
-Daegu as a city will not attract visitors. It's a good 160+ miles away from Incheon International Airport where all international flights outside of close Asian cities come. There are the typical buddhist temples, scenic mountains, etc. that you can find around any city in Korea. I used to visit family there a few times a year and I don't ever remember doing any tourism there...
-Attendance in Korea for sporting events is rather embarrassing... In America, the US national soccer team regularly sells out in large NFL stadiums. In Korea, where the national team is miles ahead of anything else in terms of popularity, a competitive fixture in Seoul draws around 30,000 to 40,000 in a 64,000 capacity stadium. Even with the national heroes playing on European clubs on the roster. People are very much content with watching on TV.