The elements of ETF are all good.

* ETF offers better diversification than a single stock in terms of portfolio and risk.
* most ETF provide greater transparency of shareholding, easier trading, higher tax efficiency and, in many cases, lower operating costs than mutual funds.
* the most common drawback is related to the EFT designed to track indexes-tracking errors can cause differences. Lightly traded EFT may also have a large bid-ask spread, and transaction costs can be a concern, according to your broker.