Safe and Effective

Safe and effective is not a lie. It's 2 lies.

However, different batches cause different effects. See faultyshot.com

Doctor: "This vaccine is safe and effective".

Patient: "However why are there so many side effects after taking it?"
Doctor: "Ermmm... it's an immune response. People react differently!"
Patient: "Ah got you! Thanks Doctor, you're the best!"