| Bundling cables, pens or loose produce so things stay together | Rubber bands contain latex, which degrades in sunlight and heat — it goes sticky and snaps. Use UV-resistant bands for outdoor or long-term storage, and swap them out before they crumble onto food. |
| Creating grip on a slippery jar lid or a stripped screw | It only helps with mild friction; a badly seized lid or a screw already rounded out needs a proper strap wrench or extractor, and a slipping band can shift suddenly and skin a knuckle. |
| Improvising a light-duty strap — holding a rolled mat, a folded tarp, a bike brake lever closed | Stretch is unpredictable and load capacity is tiny: a single band relaxes or snaps under tension and can slip off a smooth shape, so never trust one to secure anything heavy, sharp-edged or safety-critical while moving. |