Q. If you have made Qurbani before, do you have to do it every year?
A: If the conditions which make Qurbani compulsory are found in any or every year, Qurbani will be compulsory for that year. Making Qurbani previously does not absolve one from Qurbani in the future years.
Qurbani is an annual act of worship, like fasting and Zakaat. It is not a once-in-a-lifetime act, as Hajj. If the conditions that make Qurbani compulsory are found in any year, Qurbani will be compulsory for that year. Making Qurbani previously does not absolve one from Qurbani in the future years. (Raddul Muhtaar 26:211)