My thoughts
The second-system effect or second-system syndrome is the tendency of small, elegant, and successful systems to be succeeded by over-engineered, bloated systems, due to inflated expectations and overconfidence.
From the “The Mythical Man-Month”. Useful syndrome to keep in mind when “re-writing” a working system. The complexity of having parity and adding new capabilities is often underestimated.
Read the article: Second-system effect