In my 15 years of doing that work most of the time employers couldn't tell if a solution were original or not unless it was something they specifically requested. Even then most of the original work was in context of original content messaging, user interaction, and the measurements there of.
Where employers in the past really cared is in the speed of delivery. Typically speed of delivery was faster using a framework solution only if the exact solution were already written and available as an extension. In absolutely every other case software originally written in house was always faster to deliver back to the business. This is because with original software the developers are not limited by prior existing conventions. It always comes down to the prior experience and confidence of a given set of developers.
The business knows this before assigning the tasks to the development team, and that awareness (more than anything else) determines the opportunities for developers to identify their own speed of delivery. Most development teams are entirely unaware of just how thoroughly their performance is measured from a business perspective. That should be painfully obvious, because developers only cost money, and those costs go straight to the bottom line.
Where employers in the past really cared is in the speed of delivery. Typically speed of delivery was faster using a framework solution only if the exact solution were already written and available as an extension. In absolutely every other case software originally written in house was always faster to deliver back to the business. This is because with original software the developers are not limited by prior existing conventions. It always comes down to the prior experience and confidence of a given set of developers.
The business knows this before assigning the tasks to the development team, and that awareness (more than anything else) determines the opportunities for developers to identify their own speed of delivery. Most development teams are entirely unaware of just how thoroughly their performance is measured from a business perspective. That should be painfully obvious, because developers only cost money, and those costs go straight to the bottom line.