@Joe2278 Obviously your intentions are good, but that is a HUGE no-no in general, and also with AirBnB. If either guest had complained, your listing would have been shut down for a good while.
If you feel it necessary during a stay you absolutely need to check with the guest first, and literally get permission to enter the space. Otherwise, unless it's a fire or something, it will have to wait until you have no guests. I think even asking puts the guest on the spot, so I'd avoid that unless absolutely necessary.
If you have longer stays, you can include in the house rules that you'll be entering the room once a week or whatever, to change sheets, empty garbage, etc. However, if the guest doesn't want that, you'll have to work with them. Many just want their own space and to not have their privacy invaded.