The phrase "are constantly lacking" is correct and usable in written English.
It can be used to describe a situation where something is persistently insufficient or missing.
Example: "The resources in our department are constantly lacking, which affects our productivity."
Alternatives: "are perpetually deficient" or "are continually insufficient."
"Students are constantly clicking.
"We need to do things differently, as a profession we are constantly criticised for the lack of theory, the lack of application.
People are constantly complaining about a lack of real-life interaction now that smartphones have pervaded the our world.
Nevertheless, the bees and the plants they depend on, like all renewable natural resources, are constantly under threat from lack of knowledge and appreciation of these endowments.
Robert Sherman, one of Connecticut's delegates to the 1787 Constitutional Convention, expressed their concern well when he said, "The people immediately should have as little to do with electing the government as possible, because they lack information and are constantly liable to be misled".
I wash my clothes by hand; various fresh vegetables are almost a memory; my shoes are constantly muddy due to a lack of drainage and even the Russians joke that my flat is very "Soviet style".
Welcome to being an entrepreneur — you are going to be constantly battling – lack of cash, lack of customers, aggressive competition, better-funded competitors, underperforming staff, slow-moving sales cycle, or some other as-yet-unknown.
Because so many domestic violence support services are constantly fighting for survival against a lack of funding, and even funding cuts, too many women are struggling to find a safe place to escape to.
The recommendation approach using linked data increases the possibility of finding educational content from different sources that are constantly being updated, avoiding the problem of new recommendations lack.
