Oil and hyd checks
airsupport
On a 737 it is easy to check hyd qty in the wheel well, on others 747,777,767 and others it is not so easy or practical as the reservoirs are in less accesable locations, and it is normal practice to use the cockpit or remote indication.
It is good practice to physically check the engine oil at the oil tank, and do a sniff check for fuel in the oil. But unfortunately in this day and age of MOD and cost cutting the engine oil is often checked by guage on transits, and only physically at night or layover.
Old heads like myself still tend to do physical checks, but we are considered dinosaurs now, and the bean counters prefer to take shortcuts.
It only costs less than $1 per pax to have an engineer do the preflight check, but the bean counters know better than us who have been doing it for 30 or 40 years. Apparently?
GLTA !