M2 | Why we need to execute cron:run twice executing first time?

Question

I created a custom cron job and tested on local server, where it needs to run

bin/magento cron:run

two times simultaneously and then that custom job is created and scheduled.

why is it like that ?

Answer 1

Because its made to work like this.

It's from Magento documentation

"You must run cron twice: the first time to discover tasks to run and the second time — to run the tasks themselves. The second cron run must occur on or after the scheduled_at time for every task"

https://devdocs.magento.com/guides/v2.3/config-guide/cli/config-cli-subcommands-cron.html