Jono has an interesting post about ‘Wicked Problems’:

The problems then change towards being, potentially, more and more difficult to ’solve’. Reasons for this include having less, imperfect, ambiguous information, and limited resources. You have to make decisions and ‘design’ in spite of these. In the later cases the process of understanding becomes more critical than the ’solving’ itself. In the later cases different skills are required.

In short, it tends to be that problems get more difficult and complex the more contact they have with people.