Many of us believe that all of our clothes only have a one-wear potential. We can wear each piece just once before we have to toss in the dirty clothes hamper and then into the washer before we can wear it again. What a lot of people don't realize, though, is that we all have many articles of clothing that don't need to be washed after every wear.
Yes, your undergarments and things that touch you closely need to be washed after every wear, there's no getting around that. Bras, however, can be worn a few times before they're considered "dirty" and need washed again. In fact, it probably hurts it more than it helps to wash it so often. Washing bras too often can cause the elasticity to wear down and the shape to be altered. However, if you have a more active lifestyle, or spend a lot of time sweating in the sun, you may want to wash your bra after every wear. If it starts to smell, it's always a good indicator that it needs to be washed.
Something for everybody that will save people from a lot of laundry: your jeans. Jeans do not need to be washed after one wear. Denim is a tough fabric that can endure a lot and should be treated as such. You may have heard that sticking your jeans in the freezer every couple of wears to kill bacteria is enough to "clean" them and machine washing is never necessary, but this isn't true. Many people recommend, similarly to bras, that jeans should be washed after every couple of wears, but that might not be true either. Denim does need to be washed substantially less than most fabrics. Jeans can also stretch after being worn, which can alter the fit. So, leaving it up to your judgment, your jeans should be able to go through multiple wears and still be considered clean, but should be washed to avoid too much stretching, if they're visibly dirty, or, again, if they just start to smell.
Coats and jackets: articles that usually just go over the top of other close and don't make a lot of skin-to-skin contact don't need to be washed nearly as often as your other clothes, but they do still need to be washed! These can be washed about once a season but depending on what you come in contact with, you may want to opt for washing them twice a season.
Finally, you pajamas should be washed about every three to four days. Some people toss their pajamas in the hamper every night but some will wear them multiple nights in a row under the assumption that they can't get too dirty if they're only wearing them to bed. If you're the kind of person that showers at night before bed, then you can probably wear your pajamas for about a week before needing to wash them again, but if not, stick to three to four days. Our pajamas may only be worn to bed but they're still right against our skin and need to be kept clean!