Slippery customer American noun
A person, group, or company that is not worth relying on.
We should be careful with that organization. It is probably a slippery customer.
A person who is difficult to understand or comprehend his or her inner thinking,
Don’t turn yourself into a slippery customer.
An issue or individual which does not have a specific and clear definition.
I don't know how to explain it because it surely is a slippery customer.
Something that only has one of two different end results: positive or negative
To make an issue or situation less clear and less easy to understand
Used to indicate a weak and unreliable support.
If you fall for someone's trick the first time then they are at fault.
Are you going to mess with me again? Fool me once, shame on you; fool me twice, shame on me.