once bitten, twice shy

The variant once burned, twice shy is particularly common in the US, perhaps influenced by a burnt child dreads the fire.

Jawleyford had been bit once, and he was not going to give Mr. Sponge a second chance.
[1853 Surtees Sponge's Sporting Tour xxxvii.]

Once bitten, twice shy.
[1894 G. F. Northall Folk-Phrases 20]

Once bit twice shy. He had no mind to be kidnapped.
[1920 Conrad Rescue iii. ix.]

She was especially on her guard‥because she'd been victimized in a stupid swindle herself, recently. Once burned, twice shy, you know.
[1949 ‘S. Sterling’ Dead Sure xv.]

I can't imagine why this man would be harassing my wife again, Mr. Cooperman. You'd think ‘Once burned, twice shy’, wouldn't you.
[1981 H. Engel Ransom Game xvi.]

Once bitten, twice shy when thinking of certain shops.
[1998 Times 7 Jan. 27/6]

Related to: experience

Bibliography of major proverb collections and works cited from modern editions is available here.

Once hurt, one is doubly cautious in the future, as in He was two days late last time, so she's not hiring him again--once bitten, twice shy. This seemingly old observation, presumably alluding to an animal biting someone, was first recorded in 1894.