Bex

It becomes heat, in your muscles, and that is the whole answer — but the mechanism is more interesting than the destination.

On each step down, you fall a short distance and gravity does work on you, which would speed you up. You do not speed up, so something removed that energy. That something is your leg muscles contracting while being lengthened — your quadriceps are pulling to hold you up at the same time as the knee is bending. This is called an eccentric contraction, and it is your body acting as a brake.

A brake turns motion into heat. A car's discs get hot; your thigh muscles do the same thing on a smaller scale. Some of the energy also goes into deforming tendons and cartilage and into sound.

So the energy is not vanishing and it is not being stored. It is being deliberately destroyed, by you, on every step, to stop you accelerating down the stairs.

On question 2, honestly: barely, and not in the way people imagine.

Apples are mostly water and sugar. The mineral content is small, and what returns to the soil from a season of windfalls is a modest amount of potassium and very little nitrogen. You will not fertilise a mature tree with its own fruit.

What it does do, which is worth more than the nutrients, is feed the soil ecosystem — worms, fungi, beetles — and add a little organic matter. That is a genuine benefit and it is a slow, cumulative one, not a feed.

So "it feeds the tree" is wishful. "It feeds the soil under the tree, slightly, over years" is accurate and still a good reason to leave the sound ones.

"Plain savoury scones under a peppery sausage white sauce" got an actual nod from my aunt, where every previous attempt got a face.

The established term for the phenomenon is software bloat, and for the process specifically there is a better and older name: Wirth's law — software gets slower faster than hardware gets faster.

Your instinct about "bloatware" is right and it is a genuine split in usage. It started as your sense — software bloated relative to its function — and was then largely captured by the preinstalled-junk meaning, to the point where most people now hear only that. So it is not wrong, it is ambiguous, and in a sentence about an application you chose to install it will be misread.

For a single program, the phrase that survives without ambiguity is just bloated, used as an adjective: "the app is bloated". Nobody misunderstands that, and it does not carry the preinstalled implication.