It depends on the rest of your command. Echo is a client command and a special command. It will print the next parameter passed into the client's console. When you add quotes, it makes that entire string a single parameter and the quotes are stripped upon printing. As such, echo displaying quotes since it assumes they are the start or end of a parameter, so it is best to use client_print or console_print if you want to print stuff to the client's console.
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