One thing that many have yet to realise is that admins do not always use the warning script to warn players.
I personally will tend to use pm where possible if...
It looks like a new player who has made a mistake or may not realise the rules yet.
A player whos action may not be in their control such as those caused by bugs or lag.
Old players who ought to know better making a one off mistake.
The side affect of using pm is often the player who has reported has no idea if anything has been done, sorry but I am not going to pm each person that reported to say I dealt with it, I do not have the time, just trust us admins.
As you may guess though sometimes I do go straight for full warnings when its obvious from what is seen that the player does not seem to care about the server rules or others.