This is a pretty basic, unsophisticated problem...
There must be something odd about the way I type. I find that within about four months, the characters on my keyboards begin to wear out, and - first - the E, R, A and S begin to fade away.
Of course, I know where they are, and I can continue typing. But it does make a difference to typing.
I've taken to going on Ebay, and looking for a set of replacement keyboard stickers. These don't cost much (£2 - £4), but it is frustrating to get a full 'QWERTY' set when I only need to replace four characters. And then these stick-on plastic characters don't last long... Often only a month or two.
Anyone got any advice? Are there are heavy-duty characters available anywhere? Are there any other solutions?