The big problem is that it's not beneficial for IBM/Oracle/Accenture/$consultancy to quickly deliver a stable solution that works well. They make much more money by having seven layers of middle management committees vote together a crappy solution that will need five years of support/upgrades and then a replacement.
In other industries, like construction, the same fundamental problem exists, but there human lives are at stake, standards bodies have been formed to prevent it, and non-software engineers aren't outsorced to people in India who have as little knowledge as they have pride in their workmanship.
If a contractor built apartment buildings the way IBM and friends build software, they'd be sued out of existence. I mean, have you ever heard of a building project going 3x over budget and then not actually delivering a building at all? It happens relatively often with software consultancies, usually on projects so trivial (like public transport ticketing systems) that it's hard to not attribute it to malice.