The effort of army selection

Like it or hate it, army selection is a major part of Warhammer. Some people consider this a fun part of the hobby, and fiddle endlessly with lists in their spare time. These people can produce a list at the drop of a hat, which makes preparing for a game easier. Others find the selection of an army an almost insurmountable hurdle; they don't really know what they want in the army, and making a list without even a vague direction in mind is an inefficient process, to say the least. The problem is made worse when the player is hoping for the list to be competitive, or knows that they're in for a tough game. I know a few people who are capable enough players, but who find the list selection step a real stumbling block.