unproductive
abortive
barren
counterproductive
effete
empty
etiolated
failed
failing
fatuitous
fatuous
feckless
fruitless
frustrating
futile
gainless
inadequate
inane
ineffective
ineffectual
inefficacious
inoperative
invalid
lame
manque
miscarried
miscarrying
nonremunerative
nugacious
nugatory
of no effect
of no force
otiose
pointless
profitless
purposeless
rewardless
sterile
stickit
stillborn
successless
unavailable
unavailing
unfortunate
unprofitable
unremunerative
unrewarding
anguished
bonnetless
causeless
churchly
coatless
collarless
deadlier
fratricidal
gloveless
ill-considered
ill-fated
milfhunter
never-ending
purple-faced
shoeless
sway-backed
thankless