Although the trend ‘vintage’ is almost over, here are a few words regarding the wearability of old shoes.

Mainly Nike has used a material in their soles which crumbles after long-term storage.
By that I mean not just a few cracks in the paint but the entire sole is crumbling under load.
An unwearable pair doesn’t even get out the door undamaged. Compared with bread: Normal, wearable soles are as brown bread, unwearables are like crisp bread.
As a general rule:
Shoes with a window to the airpad are rather cracking since Nike has used another, worse material.
Exception to the rule is the (old) Pegasus, which has no window, but is unwearable.
A good way to determine the wearability is the “fingernail test”.
Press your fingernail into the sole on a hidden part.
If the impression disappears, the shoe should hold up.
But if the marks stays, it will be damaged if worn!
This should be tested before each use!
Something like a forever wearable pair does not exist.
That should be even more important when eventually getting doubtable pairs.
I wouldn’t spend like 300 € on a pair that can’t stand wearing or falls apart after I store them for a year.
I got cracking shoes on for an interview, they were new before and I put them on my feet sitting down. And the strain was enough to totally kill them…
As a emergency plan for doubtful pairs:
Bring a second pair in your bag to switch immediately if it should dismantle.
When it comes to buying prefer worn pairs to new or DS ones.
Due to the constant (!) movement of the material it remains soft and wearable.
(Especially long) storage leads to stiffening of the material.
Here’s an example of an old, damaged pair: