In the agents configuration, do you have any rules or restrictions on each of these pieces? Do you have them set to run during certain hours, etc?
Also, on laptops or other systems that are not on the network and if you do not have CSA / Gateway, the scan might occur on the client, but it could not communicate with the core
Not sure what version you are on... we are on 9.5 SP2
Where I control these is inside of the agent. I remember seeing that being removed or changed, not sure if that is in 9.6 or what.
If you are on 9.5, go to your agent, open it up and under "Standard LANDesk Agent > Inventory Scanner" you will have a schedule there
For Security / Vulscans, that will being the agent under "Security and compliance > Patch and compliance scan"
However you set it, you should have a bigger window than 11am - 2pm, that can create a couple issues.
One, if a system is asleep, off or of the network in that window, you miss your scan. Highly likely with laptops
Two, if all of your systems are hitting your core in that window, it can be a little hard on it (the core) depending on the number of systems and the specs of the server.
I would suggest at window of 9am - 4pm, if you are going to restrict.