Tracking elevation change and stairs climbed

I am on my third Apple watch (series 4 and now a 6) GPS cellular. None have ever worked successfully to show elevation changes over a hike or accurately showed stairs climbed. I have consulted with several apple helper bees, rebooted time after time, changed settings, rebooted Iphone 8. Nothing has helped. I know this function can work as I have seen it track close to the fitbit I want to drop on my buddy's apple watch 3.

So what can be the cause or is it some Apple watch bug or is it an Iphone issue?