Computers are problematic in large part because of the tremendous range of environments and uses:

1. Domain experts with decades of experience and highly-tuned, fixed-location, immersed interfaces. Old-school workstations. Heavy on CLI or usually really idiosyncratic GUIs.

2. More casual office users. This is your general file/task approach. I still think that could be improved, though the question is how. Having to consciously consider applications is IMO an error.

3. Mobile. Suboptimal conditions for viewing, entering, reading, etc. Some of the audio input (Amazon Echo, Google Now, Apple Siri) systems may address parts of this.

4. Appliances / controls: anything from digital clocks to DVD/BluRay players to microwaves and kitchen stoves and thermostats and washing machines. LED / LCD displays, anything from 2+ buttons to numeric keypads to dials to full keyboards. Incredible inconsistency across and even _within_ applications.

Of three sets of digital kitchen timers:

One blinks the minutes:seconds colon to indicate it is counting down, the other to indicate it isn't.

A microwave control allows use of either the timer or the microwave, but not both simultaneously.

Several chime repeatedly, others only once (and woe be you if you happen to miss the timer).

None have a count-up feature telling you _when the timer went off_.

I prefer a wind-up dial timer. Simple interface, and it's obvious when and how it's working. The bell is loud enough to hear rooms away.