Microsoft at one point wanted to become a full featured IT department for companies. From managing their infrastructures, active directory, issuing laptops, but also providing basic erp, kind of salesforce like. I am not sure where they went with that but it certainly an idea that has merit. A small or medium size company should probably outsource its IT department except for the parts that are specific to their business.

ERP are the mother of all vendor lockin for large companies. Not only you need to configure it, but you need to integrate it with the thousands of internal systems.