[fyz]

If you're trying to sell GOOG, which trades a few billion worth every day, no.

If you're trying to sell TEAM (Atlassian), which trades a few hundred million, maybe.

If you're trying to sell something less liquid (which trades a few million of notional - price x volume - then you probably want to go with some kind of algo execution.

i.e., your order size as a percentage of notional traded matters.