Inconsistency of comparator on command block

*Steps to Reproduce:
*
1. Make a repeater command block that execute an command (I made one that kill item).
2. Place 2 or more comparators to detect and light up whenever repeater command block executed.

*Observed Results:
*
There is an inconsistency of which comparators light up or neither of them work properly

*Expected Results:
*
All comparators should light up whenever the command block executed an command.