No, it doesn't. I understand that's a meme because it does happen, but "almost always" isn't just something you add to the conversation to try to make your point stronger.
SAP ERP systems fill a purpose, and they do so quite well.
There are definitely instances where a change to your ERP system is so large that it's under budgeted, or the consultants hired aren't any good, but ERP is a value proposition provided you don't f it up.
But almost all ERP systems fail? I still cannot get behind this. You're saying in 10 years the vast majority of deals you've done with ERP have failed?
If that's really true, perhaps you should do something differently. I work with many successful ERP systems. I actually haven't worked with any failures, although of course I'm aware of them because of people like you who tell me.
I trust your experience, but at the same time, it's very different than my own.
There's very little I can do to help, since ERP vendors are very risk averse. I can assure you that by the time you own a license, they've booked the revenue and moved on to the next sale. If anyone gets stuck holding the bag other than the customer, it's the consultant doing the implementation. I usually advise clients not to buy from these (and other) vendors, unless they accept the risks. They're free to self-insure against it.
As a matter of course, the CIO gets someone's foot up his ass for a year or two and is lucky to keep his/her job. Budgets are blown. Change orders flood in. Unforeseen costs. Missed deadlines. Contract remedies are weak because no one had the stomach to fight for them when they were on the table. Finger pointing everywhere. And so the world turns...
What you describe is a classic large Systems Implementor problem, and that can be very true. The A-team sold the project and the B-team deliver it. They screw up the requirements gathering and the implementation. I've seen it happen many times.
Sometimes the product is to blame because it doesn't work as promised. Most of the time the consulting organisation didn't know the product well enough and made a mess of it. Totally agree on your contract point. Agree contracts, terms and conditions up front. Pay attention and take time.
The problem with ERP is institutionalized – the licensors have set themselves up to absorb almost no risk of project failure. The big consultants are also masters of shifting risk back to the client. That leaves the client to deal with a middle tier of consultants that is a mixed bag of capabilities, capitalization, etc.