There are a few things in life that you simply can’t just ignore, no matter what rules you think are silly or customs you find unworthy of following. A few of the things on this list include eating (you have to eat to survive), consuming water, wearing clothes, and keeping up with your hygiene.
While all humans pretty much follow the first three to survive and protect themselves, there are some who don’t do the fourth. Now, sometimes that’s because of the conditions in which those people live. This is something that is out of their control and must be understood simply because they may not have running water or access to hygiene products.
But that doesn’t comprise the entire group of people who don’t follow hygiene rules. There are a select few who decide not to shower for weeks or brush their teeth ever, and this is when it becomes out of hand and can be at the fault of the person who does it.
The main reason hygiene is so important actually doesn’t boil down to societal “etiquette”, as some may guess. Rather, it comes down to health. Health is something that is collective in a society. If some people refuse to vaccinate their children, they can compromise their community at large. Just as well, if someone at school doesn’t ever shower or brush their teeth, they can spread germs or even certain infectious diseases to classmates around them.
This is why hygiene is a responsibility of people, not a luxury (at least in developed nations). By refusing to clean your body, brush your teeth, and try to keep up on cleaning your clothes, you’re not only putting your own health at risk; you’re putting the health of others around you at risk too.
That doesn’t even go to say that the social responsibility of trying to stay clean for smell reasons is another factor in the conversation of why hygiene is so very important.
So, not only are you in charge of your own hygiene because of health reasons for yourself, you’re held responsible for it because of the health of others and the daily living of others who may have to smell you and be around you. If access to hygiene and water is involved, you’ll never be faulted. But in the US, that’s not usually the case 99% of the time here in a developed country.