Does the bot calculate after every action? Using a pirate warrior deck the bot is sometimes pretty obvious: It attacks with one minion then there's a delay before the next attack and so on. The only practical reason that I can think of is to recalculate for random effects such as deathrattles.
Also, I've noticed when watching the bot that it always lingers over the minion that it attacks with or the target for a few seconds after attacking.

This bot is great - I love the options to customise mulligans and combos