When a slave does not start up the slave threads on restart, but not reporting anything to the error log about startup failures either, this can be due to skip-slave-start being set in the config file(s) or on the command line (and most likely is).

But as there is no matching variable in SHOW VARIABLES or SHOW SLAVE STATUS output this can't be checked for at runtime from the SQL level, and there is no related message in the error log either.

I'd request to at least have a message like "Skipping slave start as requested" written to the error log when skip-slave-start is in effect, but would actually prefer to have a proper variable entry for this so that GLOBAL_VALUE_ORIGIN and GLOBAL_VALUE_PATH can be checked for this setting in INFORMATION_SCHEMA.SYSTEM_VARIABLES