Why do outdoor dog beds mold in deck boxes?

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

1. 1
   Storing beds sliding under the couch instead of enclosed deck boxes to let them breathe
2. 2
   Using elevated cot-style beds for better air circulation
3. 3
   Buying beds with removable, machine-washable waterproof covers
4. 4
   Storing cushions in outdoor deck boxes
5. 5
   Wrapping cushions in heavy-duty plastic contractor bags with silica packs or dryer sheets inside deck boxes
6. 6
   Hanging cushions from the garage ceiling

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.