Idioms and Phrases with learn one's lesson
learn one's lesson
Profit from experience, especially an unhappy one. For example, From now on she'd read the instructions first; she'd learned her lesson. Also see hard way.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.