If they take a northern track, they quickly run into Saharan dust and lose their moisture. If they take a southern track, they last longer, but they still have to run the dust gauntlet and eventually run into El Niño-driven hostile upper-level winds. Ocean water temperatures in the tropical Atlantic are cooler than they have been the last few years, so there's no extra energy to overcome the unsupportive atmospheric conditions. But the hostile upper-level winds from El Niño will continue through the season. Annoying things have developed in strong El Niño seasons in the past.