Without commenting on SAP in particular, I would strongly suggest that thinking of ERP as commoditized software that has already been amortized w.r.t. R&D is somewhat wishful thinking and arises from I-could-do-it-better syndrome. My suggestion to all the naysayers out there is to do 1 of the following:
Option 1. Go build an ERP system that rocks, and beat the incumbents. Is it too hard? Can’t beat the sales/marketing budgets of big guys? Those are all poor excuses ‘cos if you are serious about how much cheaper it ought to be, you should be able to become #1 by word of mouth.
Option 2. Go sell someone else’s ERP against the guys you dislike. If you really really think there are better alternatives out there (take the flavor of the month) - then you ought to be able to sign up as a channel, and become a billionaire.
Option 3. Stop and Think. There may be a reason why very smart businessmen spend billions every year on these ERP systems.
Disclaimer: Personal opinions expressed here. And as I said, I am defending ERP industry and the customers - not the software that runs on ABAP. I had to say that - it was too easy.(This post initially started as a comment response to Thomas' post.)