Welcome to A to Z tutorial on ERP
  
Enteprise Resource Planning software is often referred to as the backbone for the entire business. 
  
Using medical analogy an ERP system has brains (process logic), muscle (business transactions), and heart (business policy). 
  
ERP system communicates (as a nervous system) across business functions.
  
ERP systems grow and evolve over time. 
  
If left unattended, it can get soft and flabby.
  
The freshly implemented system is not very stable, like your legacy system. 
  
Users might not like your newly born ERP system until it matures.