Intel's execution - as usual - was poor and lacking.
Both the Galileo and Edison were much more expensive than their Arduino counterparts, and their x86 cpu's were of little value within that space (especially at the time). Neither made it past 5 years without being killed - which is exactly what people feared. A stunning lack of long-term commitment from Intel to develop and grow a community, leaving anyone that actually built products based on their devices holding a useless bag.