what is the impact of changing log shipping schedule timing jobs? I have two severs primary and secondary log shipped server , after configuring it, I noticed that the latency of last copied file and last restored file increased and the alert of monitor sever fired a lot of times as I see it in SQL server error logs so I  modified the alert job at primary server  to fire every 15 minutes instead of 2 minutes but now I decided to reschedule the time of copy jobs to fire every 15 minutes instead of 10 minutes to decrease the the time of latency for both of the copy and restored jobs.

My question: is there any threats that may affect the log shipping process or is it normal to change the job schedule even for the alert, copy, restore and backup jobs?
As Shanky noted, this is not a problem as long as you are not actively conflicting with your own SLAs around backup/restores.

The documentation notes you can customize the jobs as needed (steps #8, 16, 21):


  Note the backup schedule listed in the Schedule box under Backup job. If you want to customize the schedule for your installation, then click Schedule and adjust the SQL Server Agent schedule as needed.