To be fair, Wilmots got them from 114th in the world ranking or something to the WC. Belgium was in absolute shambles, the FA was bankrupt, there was no organization, no proper staff, every manager with self respect said no. But instead of giving Wilmots a statue, a knighthood and a million, which he deserved, they gave him the job for more years out of gratitude, which was a mistake. Because the national team was about the only thing holding the country together, they kept telling themselves that their 2014 WC was a success, while it was obviously an underachievement.
The Belgians have been great as underdogs, in 2002 and 1986 for example. But as a football nation they can't handle the prospect of being the best with the best players. They confuse exciting matches with playing very well, like against the USA and Japan. If their talented players string a few passes together they believe it's total football 2.0. They love to compare themselves to great Netherlands sides from the past, but don't really understand what made them great from their own defensive tradition. They failed to set the bar high enough in terms what kind of football these talented players could bring if they really gelled and starting playing an intelligent passing game. Instead they declared mediocre team play with too little creativity from the collective to be the greatest art form, while congratulating themselves on being better than the Netherlands in it's biggest crisis and talent drought since 1980. As a ftooball nation they won the talent lottery and got 'sudden wealth syndrome'.
In that state of mind they got Martinez, a manager in line with their defensive tradition, expecting him to play breathtaking attacking football and when he didn't , pretending he did by celebrating some beautiful counter attacks.