Why does a cup of tea never last as long as you want it to?

It's true, a good cup of English tea, complete with a good dollop of milk, always seems to run out before the savouring has ended.

The aroma is just pungent enough, the colour a delightful peach shade and the sugar-level perfectly in tune with not-too-sweet a tooth. You work away, you sip, you chat, you sip. Before you know it you're sucked into sheer enjoyment first, then oblivion as the fast dwindling liquid in the mug before you seemingly evaporates.

You reach for another thirst-quenching swig and lo and behold, the cup is empty.

How did that happen?
Where did it all go?
Why is a cup so shallow?
Was, indeed, accelerated evaporation to blame?

So many questions, but one thing doesn't change: my cup remains empty and off to the kitchen I must trek to replenish.

Problem is: the 2nd cup is NEVER as tasty as the first.