What are the downsides of indexed annuities?

["Just a certain percentage of the account will participate in the market earnings.","Some contracts have a 5-to-10 year waiting period (Surrender Period) and there can be a fee for early termination or excessive early withdrawals.","Investment options may be less than the ones in ETFs or mutual funds, although the downside protection of indexed annuities does not exist with an ETF or mutual fund."]