The faucet, sink rim, basket, disposal, trap, and supplies can send water to the same cabinet floor.
The short answer
Clear stored items, dry accessible surfaces, and observe from a safe position during the specific use that triggers water. Stop if the cabinet contains wet wiring or if testing adds damage. Record whether the leak follows faucet operation, basin filling, draining, disposal use, or dishwasher discharge.
What to notice
Work from the trigger, not the puddle
Water during faucet operation before it reaches the drain can point the investigation toward the faucet, spray hose, base, sink rim, or supply. Water only while the basin drains changes the candidate connections. Dishwasher-only or disposal-only leakage gives another branch. These patterns guide inspection but remain observations.
Photograph connections in context
Take one wide photo showing the entire cabinet and closer images of visible moisture. Include the trap, valves, flexible supplies, disposal, and dishwasher hose without moving or tightening them. A clear picture helps the provider plan access. It cannot establish the internal condition of a valve or concealed connection.
Ask what the repair leaves dry
The scope should name the failed connection or fixture and include controlled testing. Ask whether the provider will evaluate damp cabinet material or only repair plumbing. A new trap does not correct a faucet leak, and a resealed basket does not address damaged cabinetry. Keep each responsibility explicit.
One useful question
Should I tighten every connection that looks wet?
No. Overtightening can damage parts, and water may have traveled from another point. Dry observation and a controlled test are more reliable than changing several connections at once. Stop the water and call when a valve or fitting condition is uncertain.