Milk is not a taste that any tea lover wants in their tea. Who wants something that masks the flavours pure fresh taste of the tea with a creamy taste that completely changes the texture and taste of the tea? To me, the texture of milk is the worst thing. Drinking tea is like drinking water because it has such a clean and fresh texture. Milk just fills your mouth with fat and it's a bit gross.
And yet sometimes I do put milk in my tea. Kenya teas or an assams for example, have a lovely strong taste, but it is very easy to let some of the bitter tastes come out of the leaves as it brews. Milk has the amazing property that it sucks up all the bitterness with a minimal effect on the rest of the flavour. But be clear, use as little as possible, just a tiny little amount if you need it, and none at all otherwise. And in my opinion, you should use skimmed milk. Fat in your tea is distinctly manky, and that minimises the problem. Now, I don't actually like drinking milk on its own, so maybe I am biased against it, but if you want to taste the tea, you need the cup to be filled more with tea than with milk. Otherwise just drink milk, dammit!