Cam or lifters, it's a bit like the chicken or the egg...who came first?
IF there is a mechanical failure it could be the lifters are at fault due to incorrect machining tolerances or surface finish.
But it could be the cam at fault as well if it is not in specification.
If you find lifters which are stuck and cannot rotate it is easy, then again.... they could have spun freely in the bore but due to poor machining the force provided to rotate was not sufficient while running.
Many options of failure, but only for those that fail due to a mechanical issue.
Back in the days, people bought new cams and lifter and installed them, break-in, and run them with barely any failures.
Nowdays there are soo many failed cams/lifters being reported, and at this time machining tolerances being better/precise and metal qualities being better you would expect the opposite.
The thing we fiddle too much is the oils and additives, specially synthetic oils who are not up to the job due to viscosity and/or film strength, adding magic bottles which supposed to improve protection.
Bear in mind, adding a Zinc additive does not mean it provides protection instantly, it will adhere to the metal surfaces over time and only then will provide protection when metal to metal contact occurs. This is not happening in those first 20 minutes of break in. (it is there to prolong the oil life, as oil is used the viscosity degrades and looses film strength)
The right oil that provides good film strength will protect better as its ability to maintain an oil film between these parts that are pressed together is good and therefore avoid contact at all times.
(Running stronger valve springs with big cams increases the force applied and require a higher film strength)
That's where the moly paste comes into play, this is there only for the time the engine cranks and fires up and no oil flow is present yet but will follow soon after (therefore priming is a must to shorten this time)
There are many reputable engine builders who use Comp cams as well and have no issues with them.
They use old fashioned dino oils, remove the inner springs (if applicable) and run it for 20 minutes and never worry about it.
I think those guys are the best source for asking what to use, here are many guys who had success with certain mixtures of oils and additives, but it comes down the line that just a simple oil selection that provides the film strength needed to avoid excessive wear during this critical break in period is all it needs.
Which is the same thought as they did in the 60's and 70's with these engines.