Description of problem:
The default delay value for random_sleep is 360 minutes, which means yum-cron can be delayed by up to 6 hours. That is far too long for a job that runs as part of /etc/cron.daily! The /etc/cron.daily/0yum-daily.cron script is one of the first ones run (after 0logwatch), so everything else gets delayed by a random but often excessive amount. If the delay is somewhere around 2-3 hours or more on a Sunday morning, logrotate will run so late that the following Sunday there's a high likelihood that it will conclude that the logs don't need rotating because it hasn't been a full week yet since the last rotation.

A far more reasonable maximum for the random delay would be in the 15-30 minute ballpark.

Version-Release number of selected component (if applicable):
3.4.3-150.el7.noarch

How reproducible:
Because of the random nature, it's hard to reproduce consistently, but if you look at /var/log on a number of RHEL7/CentOS7 systems that have been running for a few months, you're likely to notice gaps in the rotated logs, with some Sunday's results missing or delayed to Monday.

Steps to Reproduce:
1. Ensure that yum-cron and logrotate are installed on your RHEL 7 system.
2. Let stand for a few months.
3. Examine which /var/log/messages-201* files are present and see if any Sunday rotated logs are missing, or possibly delayed by a day.

Actual results:
-on a few of my systems:
/var/log/messages-20170313
/var/log/messages-20170319
/var/log/messages-20170327
/var/log/messages-20170402

-on another:
/var/log/messages-20170312
/var/log/messages-20170320
/var/log/messages-20170326
/var/log/messages-20170402

Expected results:
/var/log/messages-20170312
/var/log/messages-20170319
/var/log/messages-20170326
/var/log/messages-20170402

Additional info:
This is on Scientific Linux 7.3, but it's built from the same sources as RHEL and CentOS, so I expect the same issue is occurring on any EL7 system. After discovering the cause of the problem, which took some time to track down, it was an easy fix to edit /etc/yum/yum-cron.conf and set random_sleep to a saner value, but the default value shouldn't be set to something that breaks things.