It’s a relatively easy path from having a diversified portfolio to a diworsfied one. Here’s an article that illustrates the pitfalls of diversification done wrong.
“Many people have numerous funds in the portfolio. A few have as many at 40, but 20-30 is not uncommon. This is partly due to the historical method of selling mutual funds, as the distribution agent was incentivised to push new funds,"
Sanjiv Singhal, founder and COO, Scripbox,