A: I’ve heard that Jamie will drop his research project.

B: Really? He’s not someone who does anything in half measures.

A: Perhaps he doesn’t want to, but the investors have withdrawn their funding for the project.

Note: This idiom means “a partial, halfhearted, or weak line of action.” Half measure is literally half of a full measure of something. Originally, the expression was probably coined by drinkers in a pub or bar, who were unhappy with bartenders giving them only “half measure” of a drink.