This seems like quite good general repair advice. I use zip-ties for lots of things, but it's obvious they are brittle and I've had a few break after years exposed to vibrations and "the elements". (I carry many spares, obvs, as they weigh almost nothing). So they're great things ... but not perfect!
I have a couple of retro-tastic toe-clip straps in use currently. No plastic, no velcro!
Yes alot materials used today have some cost cutting in their production, that is, less or just lack additives that make them durable against "the elements" (UV from Sun etc).
That's how I arrived at "out of the commercial box" solution that uses things out of their normal application, alike the washing line I mentioned here.
On my rear rack I put a shelf of a fridge, it's secured in place with inner tyre. If it gets a hit nothing breaks - it veers back.
I extended the rear rack with a second one, mounted with knotted textile lint (from window frames temporary manipulation until placement) with several windings as to spread the load over more crossings of the fridge shelf.
And the original mudguards, this topic, that came loose or broke at mounting positions, I repaired it as described earlier: by moving the parts to an overlap, connect these by drilling holes for bent pieces washing line, compensating for the lost length due to the overlap, by adding a piece from a broken I found between garbage, and drilling holes on right (new) positions, to mount them same way to the frame.
And nothing rattles, since every mechanical connection goes along an elastic material, which absorbs the OhNo Vibrational Energy.
Total Cost:
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