While a layered approach is important, there comes a point where "more is less".
If one runs too many security applications (especially in real-time), the likelihood of potential conflicts/clashes/slowdowns or other performance problems increases. Without knowing the specs of the system in question, it's hard to say.
And Kaspersky products, in particular, can be finicky about having too many, conflicting security applications installed.
With increasing numbers of installed/running security applications, there is more work/interaction for the user to keep them updated, configured, compatible, etc.
Moreover, no one security application or combination of applications can protect 100% of computers 100% of the time from 100% of the malware in the world.
As mentioned in my earlier reply
here, the most important computer security component is the one between the chair and keyboard. A user who is determined to become infected will do so, no matter what security programs are installed.
The references and resources offered in that earlier reply provide extensive information about safe computing practices, security application selection, etc.
Cheers,
MM