If it gets deposited, it means that it’s not in the water any longer, or at least the concentration in the water has lowered. What you can taste is already in the water before you boil it and does not come from the kettle (well, in kettles that have been used normally with normal water).
If it bothers you, just boiling a bit of slightly diluted vinegar will get rid of it.
> If you care about energy efficiency, you should descale your kettles every so often.
It's not even hard, just boil a solution of 1/2 white vinegar + 1/2 water, and the CaCO3 (+ 2H(+) from the vinegar) changes back to Ca(2+) + CO2 + H2O
You can even see the bubbles from the CO2
I'd recommend using citric acid instead, they sell it here as "lemon salt" so it comes in an easy to use salt shaker. I usually put it in the minimum amount of water required to safely boil it and a small amount depending on how heavy the deposits are (usually up to a spoon is enough for me), though you could also just pour it in and wait.
It works really well and doesn't leave the same smell. When I'd previously used vinegar I'd had to boil another round of water and throw it away just to clean the kettle from the vinegar itself, but with citric acid there's no need (just don't drink the citric acid, it tastes like acid :)).
Do you recommend citric acid over vinegar just because of the smell?
I use vinegar all the time, put in something like 50 ml to the remaining hot water just after making a tea. After a few minutes you can just rinse it and let it evaporate, 5 more mins and the smell is totally gone.
Good thing too, because if you drink demineralised water it pulls electrolytes out of your cells (I think by osmosis) and eventually you also end up with decreasing bone density.
If you care about energy efficiency, you should descale your kettles every so often.