Steve Jobs single handidly killed Apple's presence in the early PC market by taking his project (handling the development and launch of the first Macintosh) and commandeering it into a monster project.
What was meant to be an affordable alternative to the Apple II, became under Job's supervision a method to take control of the Apple line of computers. He ended up making a less feature-rich Apple II, which rivaled it in price, killing the idea that the computer could compete with other cheaper computers on the market.
Yes, it was a disappointment. It lacked color (something the Apple II already had), had buggy software, and all at a price that rivaled the Apple II.
$1,298 for the Apple II
$2,495 for the Macintosh
It completely destroyed the progress they'd made. Jobs took this project opportunistically at a time when Steve Wozniak was recovering from a plane crash. If he'd approached the project more strategically, it could have positioned Apple to take a place in the market share of cheaper PC's of the time.
What was meant to be an affordable alternative to the Apple II, became under Job's supervision a method to take control of the Apple line of computers. He ended up making a less feature-rich Apple II, which rivaled it in price, killing the idea that the computer could compete with other cheaper computers on the market.
All to stroke his own ego.