I assume they have decent leaf growth. They could well have suffered last year when they were making new flowers. if the leaves are not distorted give them a decent feed when it warms up a bit and keep them well watered and fed. If the leaves are distorted lift and destroy them.
occasionally they will have a year off and come up blind.

Happened to me one year and one good watering with Miracle Grow just after the flowers that did appear died back did the trick - back to full strength the following year.
The cause of the poor showing htat year was a very dry spring so Sbg's advice re watering should be taken unless the weather goes on being so wet.

Do you leave the leafs on after flowering? If not that means that the plant can't photosynthesis and the the energy generated from the process will not be down in the bulb for next year's growth. I feed them banana skins.

yes you must leave the foliage until it starts to die back naturally. don't fold them over either as this encourages mould growth.