My company paid over the years over 1 billion dollars to SAP and the amount is increasing as the time goes by. What I learned in ~ 6 years in the IT areas using SAP is that the quality of the design and the quality of the implementation are critical for success, while a very strict change management process can keep it alive. Mediocre consultants doing the implementation are one of the biggest problem; SAP is not that hard, but definitely not simple, a few good architects are critical, getting unqualified consultants by the dozen is bad and moving code to production without very thorogh testing will kill it (no CI/CD, it's not a game to play it with bug fixes coming on a daily basis).