Why should you care about them?
Multiple SQL Server Agent jobs are configured to start simultaneously, which will not perform as fast as if jobs would not overlap.
Your SQL Server may be under heavy load for short bursts of time.
How can I find the SQL Server Agent jobs that start simultaneously?
You can use the script below to list all SQL Server Agent jobs starting at precisely the same time.
SELECT j.name AS JobName
,j.description AS JobDescription
,a.start_execution_date AS JobStartExecutionDate
FROM msdb.dbo.sysjobs j
INNER JOIN msdb.dbo.sysjobactivity a ON j.job_id = a.job_id
WHERE j.enabled = 1
AND a.start_execution_date IN (
SELECT start_execution_date
FROM msdb.dbo.sysjobactivity
GROUP BY start_execution_date
HAVING COUNT(*) > 1
)

How to fix them?
- Spread job execution tweaking the job schedules.