Apple Home automation not working consistently

“When the last person leaves home” Automation does not consistently work, intermittent at best. My wife & I have our location services on and our iPhones designated as our primary “location devices”. When we both leave home, whether we’re walking or driving. The automation will not execute about 90% of the time. If I delete the automation and rewrite it will execute at least a couple of times and then become dormant again.

However, “when the first person arrives” automation runs it works every time whether the “last person leaves” works or not.

Could anyone shed some light on anything I’m missing.

Thanks.

[Re-Titled by Moderator]