Why would anyone go and destroy their career by sabotaging an employer? Such person is clearly can't be trusted cause god knows what they do if they think their

Why would anyone go and destroy their career by sabotaging an employer? Such person is clearly can't be trusted cause god knows what they do if they think their boss is an asshole. I quit two times not on the best terms with the management and the only "sabotage" was a zero-day notice and a two-week notice. It just never crossed my mind.