A bad custom is like a good cake, better broken than kept.

The proverb urges people to stop an established practice once they recognize that it does harm. Familiarity alone is no reason to keep doing something.

Its cake comparison gives a playful turn to the advice: breaking something need not be a loss. In the case of a bad custom, breaking it is the point.

Use it to challenge an argument for continuing a harmful practice merely because it has become customary. The cake image can make a firm recommendation to change course sound less severe.