We find strong evidence of decreasing returns at the industry level: As the size of the active mutual fund industry increases, a fund's ability to outperform passive benchmarks declines. (papers.ssrn.com)
In fact, every program we offer is established to increase adoption rates and decrease return rates. (ltbhs.com)
In other words the investor has essentially increased risk while decreasing return, the opposite of what investors should be trying to accomplish. (investopedia.com)