It's called a continued revenue stream.
If the Jab gave 100% immunity, then there'd be no follow-on revenue. But needing a booster every six months? GOLDMINE!
Need jab on the 1st of each month, booster on the 15th of each month. More billions in profits!
As long as the public keeps imagining these shots are actually vaccines and confer some sort of immunity - should be easy - many in the public have no idea what the word ‘vaccine’ actually means.