Chain stretch

Chains don't stretch. The pins wear thus making it seem as if it has grown longer. If the chain is at the 1/2 way mark, it is worn that much thus the potential for breakage is 2 times as much. Removing a link can be done and I have years ago but it won't match the sprockets anymore and will wipe them out in a heart beat. If the rider is lucky, the chain will just roll out the back. If not, it can bunch up around the counter shaft sprocket destroying the cases or wind around the rear wheel locking it up at speed. Given the price of a chain verses a wrecked bike and or injury even death, is a cheap price to pay. If you can't adjust it anymore, replace the chain and sprockets.
"Live to ride and ride to live."
Steve

Yes, amazes me some of the horrors I have seen in the chain and sprocket department...not just on
50cc 125cc learner bikes either.

Trivia: kawasaki first invented the cutaways on the links to reduce weight. i.e. the old design was like
O the kawasaki design like 8 .