I get one bulb, one flower. Maybe mine aren't that happy where they are, they seem to DECREASE in number over the years. Do the slugs get them, or the rabbits? Or are they in the wrong conditions to really flourish?

One bulb, one flower. They are not that easy to get to repeat flower in the following seasons, mainly because the bulb exhasuts itself flowering. Trouble is you need to heavily feed at the right time, which is before the flowers appear. At the price they are these days, you can replant every year for little cost and wait for the old bulbs to regain their strength.

I lost mine after about 3 years,but thought it was due to excessive wet,that winter,and think they rotted.As Owdboggy,says they are quite cheap to replace
these days.

mine are up and flowering for the third year running. I dead head it as son as it is finnished as i am not after the seeds head.

Deadheading and feeding are the secret to getting Alliums to multiply, as is excellent drainage--it's a bit wet in the UK for most of the big Alliums. In the beginning, though, it's one bulb, one flower head. It might be worthwhile planting them in clumps about 30 cm apart.