Depends what's meant by "core". If you're a cake business, don't outsource cake making, but do get someone else to build your shop. But so many web companies

Depends what's meant by "core". If you're a cake business, don't outsource cake making, but do get someone else to build your shop. But so many web companies spend time and energy building CMS, db astraction layers, and tonnes and tonnes of infrastructure that is nothing to do with their business.