Originally Posted by
Zfz
I don't know about the bots in FFXIV, but I remember reading about such bots in PSO2 already implementing a bottom line below which they will not undercut; instead they will buy up items sold at very low prices and add it to their stock. The same kind of 24/7 bots, updating their prices every couple of minutes.
Essentially, bots with a simple flow-control already exist and will maneuver around simple tricks like that. Their strength isn't in how smart they are, but how persistent they can be, watching the board and undercutting or buying out stock 24/7, while operating at a very low profit margin that a human player would otherwise consider unprofitable.
Even worse. There may be bots operated by RMT vendors who use the market board to launder their gil. Use dirty gil to buy up mats, use bots to make items, then use bots to sell those items (sometimes even at a loss), and you get "clean" gil.