A market order is never a good idea especially in the otc unless something really bad or really good comes out and you don’t care what price you get in or out at. With that said I know E*TRADE does not even allow a market buy on OTC stocks. I’m not sure about other brokers on that.
A market sell or buy will not get done quicker than a limit order put in at a price that is available on the bid or ask. If you market sell the share price will drop much quicker and you will end up selling way lower than you would if you had put shares in smaller blocks in the ask. After these market sells you’ll notice the share price usually recovers within minutes. Everyone sees it as an opportunity and they are happy to buy up the shares you sold too low.
May I ask what brokerage gave you that advice and was it in the context of some big news coming out? It’s definitely not good advice otherwise.
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