We covered this topic in an earlier thread and this one too.

"My best advice to those confused about the time factor and the need for survival curves and Kaplan-Meier analysis is to do some due diligence. Google. PubMed. Wikipedia. Etc. I provided some links below. I'm sure there are some tutorial videos too. 

BearDownAZ

Understanding survival analysis: Kaplan-Meier estimate

The analysis of survival data: the Kaplan–Meier method

Wikipedia Kaplan–Meier estimator

Why Use a Kaplan-Meier Analysis

A PRACTICAL GUIDE TO UNDERSTANDING KAPLAN-MEIER CURVES"