The origin of the products line in R/3 is an architecture whose functional and technical bases are 25 years old. During these years the product has been changing and evolving on these bases.
The compatibility of the functionality maintenance in each version is a burden that does not allow for some aspects to re-engineering.
SAP S/4HANA inherits most of the functionality and logic of ancestor but in some aspects it is disruptive with the consequent impact on the passage from one product to another..
