Why the recommendation is usually the mild one
Manufacturers and conservators keep naming the weakest thing that works, and it is a decision about irreversibility rather than caution.
In detail
One pattern dominates the authoritative care documents: the first-line instruction is almost always soap or a mild detergent in warm water with a soft cloth, and the strong products appear only as narrow, conditioned exceptions. That is not timidity. Cleaning is a comparison between two rates — how fast the soil comes off, and how fast the surface underneath is altered — and the second is usually irreversible while the first is repeatable. A mild method applied three times removes as much soil as an aggressive one applied once and alters the surface less each time, so the gentlest effective option is the one with the best worst case. Two corollaries follow. ESCALATE ONLY WHEN THE MILD METHOD HAS ACTUALLY FAILED, rather than starting strong to save a step, because the strong step cannot be un-taken. And when a document does permit something aggressive, read the conditions attached rather than the permission: a vent hood manufacturer permits a non-abrasive scrubbing pad and puts a gritty washcloth on the same prohibited list as steel wool, which is a statement about how narrow the permission is.
Why
- Soap is explained by Why the recommendation is usually the mild one
- Detergent is explained by Why the recommendation is usually the mild one
- Water is explained by Why the recommendation is usually the mild one
- White spirit is explained by Why the recommendation is usually the mild one
Sources for this page
Sources
Whirlpool Corporation · Manufacturer documentation
Relied on for: That the primary instruction is soap, water and a soft cloth or sponge, and that gritty washcloths and abrasive paper towels appear on the same prohibited list as steel wool pads. (states this directly)
Conserve O Gram 7/1: Cleaning Wood Furniture
National Park Service, US Department of the Interior, 1993 · Government or regulator
Relied on for: That cleaning is performed only as needed rather than on a routine schedule, that a solubility test precedes it, and that the soap step is reserved for a second pass on stubborn dirt. (states this directly)