Hold'em table

Q6 offsuit is too weak to open from the button for a full bet, and calling does not close the action. Folding preserves the stack for better spots.

Heads-up against just the big blind with a suited Q3, a small raise builds the pot and applies pressure.

6-8 offsuit is too weak to call a 2.5x raise out of position heads-up, and it plays poorly postflop. Folding preserves chips for better spots.

As4s is a decent suited ace on the button; raising to build the pot and take advantage of position against two limpers/blinds.

Ace-four offsuit is too weak to call a 3x button raise with the big blind still to act behind me; I'm dominated by stronger aces and out of position.

Q2s is too weak to continue out of position against a button raise; dominated queens and poor postflop playability make folding the higher-EV line.

Nine-three offsuit is one of the worst hands and calling 100 into 150 has poor implied odds even in position 3-handed. Folding preserves chips for a spot with real equity.

K3o is too weak to complete or raise out of the small blind against the big blind, so folding limits the loss to the posted blind.

43 offsuit is too weak to open from the button in a three-handed game, so folding preserves chips.

68 offsuit is a weak, disconnected hand from the first-to-act position in a 3-handed pot; folding preserves chips for better spots.

42s is a very weak hand heads-up. Completing 50 to see a flop with a hand that rarely connects is not worth the investment against an unknown opponent. Folding preserves chips for better spots.

6c5d offsuit is a weak hand with poor postflop playability; folding for one big blind avoids playing a marginal spot out of position after the flop.

94o is too weak to play out of position for a raise or a call; folding the small blind is the lower-variance choice.