It's so much this. Intel showed up with a proprietary 70 pin fine pitch SMT connector, a 1.8V power requirement and sold the Edison to high level designers, when the market they were after (the Rasp-PI folks) had extremely easy to integrate fat header pins that are 5V tolerant and beginner friendly. You needed a breakout board and hours of tinkering to get the thing to a state that you get out of the box from the ARM offering.

Galileo was as close as they came to a home run though. It really was their run at a Rasp-pi-alike, but it was almost twice as expensive, wasn't compatible with the Rasp-Pi headers (though it oddly was with Arduino, which seemed like a real design impedance mismatch), and was lacking numerous peripherals like video out.

They had a similar problem with that whole Maker-targeted series of chips - they couldn't seem to decide if they wanted to capture the ease of use of Arduino or the deep integrator capabilities of these target-specific MCUs and really failed to split the difference.

They also failed to take into account that they were very much the minority player and any sort of entry into those markets would be a war of attrition and not just overnight success... and the billion dollar juggernaut did what billion dollar juggernauts do to side projects that aren't overnight successes - they killed it before anyone could even develop competence working with them.

Both Edison and Quark really had niches they could have well serviced, if they had given it a real try... but it was very apparent that management wasn't interested and the designers didn't understand who they were targeting.