underutilize
On the whole, this life-saving therapy is under-utilized, rather than over-utilized.
They found that the people who overutilize health services are rich people.
The tax bias against equity is so significant that corporate managers have little choice but to over-utilize corporate debt.

SMART Vocabulary: related words and phrases

Using and misusing
adopt
adoption
avail
avail yourself of something
be/go heavy on somethingidiom
exhaust
give/allow something full playidiom
go into something
go through
gobble something up
make capital out of somethingidiom
spare
spent
swallow
tap
turn to someone/something
turn/use something to good accountidiom
unblock
underuse
underused