Check where wood meets the ground or a hard surface. Steps, columns, porch skirting and the bottoms of siding boards fail first because they stay wet the longest.
Probe soft spots gently with a screwdriver. Paint can look perfect over wood that has lost its structure underneath.
Watch window and door corners. Blistering paint, staining or joints opening up usually means water is getting behind the trim.
Look up as well as down. Failed flashing and clogged gutters send water into fascia, soffit and rafter tails where nobody notices it for years.
Address the water source with the repair. Replacing damaged wood without fixing the leak simply resets the clock on the same problem.