You have two systems, so you need to write a layer of glue code to make them work together. The glue code turns out inelegant, spaghetti-like, hard to work wit

You have two systems, so you need to write a layer of glue code to make them work together. The glue code turns out inelegant, spaghetti-like, hard to work with. So you spend a little bit of time cleaning it up, abstracting reusable things out, and generally systematizing things. Now you have three systems, so you need to write two layers of glue code to make them work together…