Yet another onsen question

Hello,

after having been to quite a lot of onsen & sento, I thought that I understand the procedure by now. However, after stumbling over the "How to take a bath?" instructions here, I'm a bit confused.

So far, whenever there was a designated washing area, we (me and some Japanese friends/colleagues/..., who should know the procedure) washed thoroughly at first, then entering the bath(s); at the end, only rinsing slightly.

Now, I read here on japan-guide that you're supposed to just rinse, then entering the bath, then washing, then into the bath again.
Which, for me, doesn't make any sense at all!
You wash to get clean. So, either you were clean from the beginning (after rinsing), which would render the 2nd washing unnecessary, or the rinsing was not enough, in which case you also dirtied the water.

I know that there are places where you can rinse only, but I'm talking about the standard onsen/sento here.

Thanks for your input.

Traditionally, you just rinse, then soak, then soap. But in today's hygiene obsessed society, more and more younger people chose to soap before entering the bath. Customs are changing constantly from generation to generation.

What you do is the proper way for hygiene. But in a cold winter, who wants to soap up & scrub in the cold bath room. Some places are freezing. So people become lazy & rinse off quickly, soak, be still & warm up for a few min., loosen up some dirt/dead skins and before they fall off in the bath water(wishing), jump out, soap up & scrub, then go back in & melt away relaxed in the onsen. Then, rinse off before you leave the bath room. Never put any bath water in the mouth. As long as you don't wash in the bath tub, nobody cares. That's why I only go to once through water onsen, like Hakone & other well known onsen towns where the abundant scalding hot geothermal water comes out and not reheated/recirculated like ones in sento or Tokyo onsen places where they may change the water only once a week or less after perhaps thousands of people have gone through.

OK, thanks to both of you, this actually makes sense.
Yet I still think this explanation would be worth adding to the japan-guide "How to take a bath?" instruction page, since this website is a great source of information for many people, and then they might wonder why basically everybody around them behaves differently. ;-)