I have had two bikes stolen, both in England, the vehicle crime capital of Europe. I always figured it was usually a opportunist thing, so just making it a bit more difficult would be enough.
The first was stolen from the centre of Bedford in the afternoon. I had it chained to a steel railing with a lightish chain, though a medium sized set of bolt cutters would have freed it, and probably did. No opportunist that one.
I had a more substantial, hardened chain for the second, which I carried around the grab rail and over the seat. It was clearly visible, and easy to drop though the back wheel and locked for a short stop. For a longer stop it could be removed and so I could chain the bike to something solid. It was stolen when I had just ducked into a newsagent for a few minutes, so had not bothered locking the chain or the steering lock.... though of course I took the ignition key out and had it with me. Some opportunist had that one.
Where I worked at the time I kept the bike in a locked shed in the farm yard, about 20 metres from the mobile home I lived in. We had a large trailer go missing from the farm yard, but did not realise it until a few days later when we wanted to use it, and were trying to work out where we left it!
Here in Thailand I doubt that anybody wants a 14 year old Honda Dream. I just lock the steering, and keep the bike under cover where I live.
In NZ, the same. I have never done any more than lock the steering.
For one of my bikes, a Suzuki TS 185, I did not even do that. In rewiring the bike I had not bothered with the ignition switch, so it did not need a key. In the several years I had it, no one wanted to steal it. I did not like that bike much, and frankly it would not have bothered me if someone did!