Many moons ago I was walking across a light aircraft apron, (with my hi-viz on!), when I observed a Cessna 152/172 taxiing, and actually dragging along the tie-down weights hanging from each main-wing, I kid you not.
I waved my arms to stop the aircraft, which it did. I then thought, how do I convey the problem? I pointed, then stood there, holding each upper arm out horizontal, and doing an up and down motion as if I was lifting a heavy shopping bag in each hand, or doing dips on the parallel bars.

The "pilot" understood, and gave me a big thumbs up. Walk around? what walk around?! Hopefully a lesson learned by him.

I think DAR is suggesting locking controls with something at the moving surface, rather than in the cockpit. NOT suggesting no lock at all.

I suspect he is too. But then there is real world. Real world is.....no external locks for most aircraft and not easy to get. Perhaps for a personal aircraft one can do it but for me, renting from a bunch of locations in the last few years.....only one with an external lock provided......a rudder lock for a Grumman Cougar in New York, which was kept in a hangar.

Cessna 182A, 'hadn't flown in a month or so, owner left it, and asked me to pick it up. Cessna control wheel lock installed. Did my walk around, but did not notice that one aileron pushrod was bent. The effect was to droop the aileron. It took off great STOL with a drooped aileron, but the control wheel was well over in flight. Aileron system inspected, pushrod replaced, ailerons rerigged, and it was fine.

Cessna 150M, 'hadn't flown in many months, let at YYZ. Owner wanted it flown out so as to no longer incur parking fees. Cessna control wheel lock installed. Did my walk around, everything looked normal. Everything seemed normal in flight, until short final, with full flaps extended. I went to flare, and the control wheel jammed in pitch. A desperate and hearty pull released the jam, and I landed with no grace whatever. In cruise flight, the hole in the control wheel tube is "outside" the plastic bearing in the instrument panel. When you retrim after extending full flaps, that hold goes just inside the plastic bearing. I had not noticed that there was a burr around that hole in the tube from the controls banging it for months at Toronto. The burr had caught on the inside of the bearing just enough to jam when I was pulling back and up on the control wheel. (My pre flight control check had been done without lifting the control wheel up, so the burr did not catch - the bottom seemed not to have been burred). I carefully filed the burr off the hole, and it was fine. I had the plane inspected anyway.

In both cases, knowing what I was looking for preflight would have revealed the defect, but, in both cases, I was not looking for that - now I am! Locked control surfaces, and free cockpit controls assure zero risk of flight control systems damage from winds on the flight controls.

The Cessna family had a simple yoke lock with a pin running through the control column.

I don’t know why by Piper never adopted this system which would have overcome the loose tailplane in winds. I was like many taught by flying instructors to lock the controls using the seat belt method. The same instructors saw three Tomahawks on their backs after a gusty night.

The ubiquitous small concrete blocks or five gallon water drums are locked to aircraft around the world assuming these will defend a forty knot gale gusting sixty. Outside parking demands locking the aeroplane to the likes of steel cables seen in airports across the USA.