Handle Bar Clamp Bolt

started on the task of changing the fork seals on my tiger and straight into trouble!
The long bolt holding the handlebar clamp was seized. I was able to turn it 3 or 4 times then stuck, the clamp was loose now. I could screw it back in 2 turns then it stuck again, could turn it 2 times in and out but no further. Applied DD’s bolt I un seizer to no avail, finally decided to gently but forcefully apply pressure and eventually little by little it came out and this is what I saw

The thread inside the yoke had “welded” to the bolt. I had to chip it out with a small screwdriver. I have had these bolts out a couple of times over the last year and copper slipped them but obviously to no avail! Luckily it will go back in and tightens up but what the F*#k are you meant to do to prevent this? Doesn’t bode well for all the other bolts I’m going to have to undo.