From an article titled "Administration foiled by own Iraq goals" in the LA Times:

The Bush administration's decision to set benchmarks for measuring the progress of the Iraq mission is now seen by some U.S. officials as a costly blunder that has only aided the White House's critics in Congress and its foes in Iraq. Administration officials saw them as realistic goals that would prod the Iraqi government toward reconciliation, while helping sustain political support for the effort at home. The yardsticks include steps vital to Iraq's stability: passage of a law to divide oil revenue among the key communities, reforms to allow more members of Saddam Hussein's party back into the government, and elections to divide power in the provinces. Yet now, with the major goals still out of reach, the administration is playing down their importance. With an interim report on the U.S. effort due out today, administration officials instead are emphasizing other goals” some of which are less ambitious but have been attained. Ryan Crocker, the U.S. ambassador to Iraq, recently told reporters that while the benchmarks remain important, "We have to look on a wider scale than the benchmarks themselves." In private, many officials were more scathing in their critique, saying that defining the goals in such a way galvanized resistance in Iraq and gave war critics a way to argue that the U.S. mission was falling short.

I think this is a fine illustration of one of the big problems. These guys see this as a game. Therefore, they think that defining goals was a mistake because it has aided war critics in arguing that the effort is falling short. The problem isn't how short the effort is falling. It's that people know how it is failing.