Final Rinse?

I bought some liquid fabric softener at the store the other day. Usually if I bother with fabric softener at all, I use the dryer sheets. I was going to use it for the first time so I read the direction to see what you even do with it. It said on the directions to add the liquid to the washing machine's final rinse.

This really perplexed me. How am I supposed to know when the washer is beginning the final rinse? Am I supposed to have some innate washing cycle sense? Should this be a part of my womanly instincts? Even more ridiculous, am I supposed to keep an eye on it so I know when it's coming? There are plenty of times I forget I even put clothes in the washing machine at all. Is the washing machine supposed to let me know one way or another when the final rinse is happening? Is there a buzzer of some sort? I just stood there as the washing machine filled with water not knowing what I should do. Should I call my mom and ask her? Maybe my mother-in-law or my friend who has an answer for everything household related.

Finally, I just decided to pour it in at the very beginning when I put the detergent in. What's the worst that could happen? And then I forgot about it. I forgot about it because later that evening I put a shirt on that had been freshly washed. It smelled better than our clothes usually smell. I was honestly confused about why this shirt smelled better. Had this shirt ended up with Jackson's clothes somehow and gotten washed at my mother-in-law's house? Then I remembered the liquid fabric softener that I put in with that load of laundry. I don't know if the shirt was actually softer or not. Probably not.