Often when a person needs or wants something, instead of coming out and asking for it directly, s/he only hints at it.

Hints do not motivate.
A hint does not convey a message and does not deliver an impetus to act.
The listener may even feel irritated, as subconsciously s/he expected to hear a request and its implicit compliment, and was disappointed not to receive it.
—
So why do people drop hints instead of asking?
People don’t like to need someone else, so they don’t ask outright for help.
Hinting displays unbridled vanity. A person may need something, but shies away from the unpleasant feeling of having to ask for help. He might hint. Or make demands, which he feel keeps him in control of the relationship.

Additionally, he fears that making a request will ultimately increase his indebtedness toward the giver. Since he does not want to be obliged to return any favors, he either hints and constructs a scenario in which the other acts purely on his own initiative. Or makes demands.
—
Instead of “That coffee smells so good.” or “My cup is empty”, ask directly “Can you please get me a cup of coffee.”