They're not big enough.

SOURCE

Yeah, I had to look it up...

palimpsest |ˈpalimpˌsest|nouna manuscript or piece of writing material on which the original writing has been effaced to make room for later writing but of which traces remain.• figurative something reused or altered but still bearing visible traces of its earlier form: Sutton Place is a palimpsest of the taste of successive owners.
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