Liability
li·a·bil·i·ty ˌlīəˈbilədē/ noun
- A person or thing whose presence or behavior is likely to cause embarrassment or put one at a disadvantage.
- A person who gives a lot of promises, but never keep them. Note that this word is inapplicable to strangers.
- Unreliable "pal", who WILL NOT support you in serious situation.
"He's just a liability, he'll never show up"
"He has become a political liability"
"You're a fcuking liability"
"You are being a liability"
It means you do not provide enough positives to outweigh the negatives which overall means you are less than useless, a loss of profitable engagements and you do not want to be labeled as a liability ever, ever again. Be the Asset in your life style.
It means that you are putting something at a disadvantage and that your actions/participation might lead to failure of the task.