Efficacy matlab sirf ek term hai jo ye batata hai ki koi product ya ingredient kitna accha kaam karta hai apne intended effect ke liye defined conditions mein. Ye koi actual skincare ingredient nahi hai isliye iska koi chemical function ya side effects assign nahi kar sakte. Basically jab hum kehte hain kisi cheez ki efficacy acchi hai, to matlab vo apna kaam properly kar rahi hai.