Timing matters!

How long is an instant? The answer, of course, is ‘it depends’, but I’ve been finding it fascinating playing on the demo page for AngularJS tooltips. and seeing what feels like ‘instant’ for a tooltip.

The demo allows you to adjust the md-delay property so you can change the delay between hovering over a button and the tooltip appearing, and then instantly see what that feels like.

Try it yourself, set a time and then either move over the button as if you were about to click t, or wondering what it does, or simply pass over it as if you were moving your pointer to another part of the page.
 
If the delay is too short (e.g. 0), the tooltip flickers as you simply pass over the icon.
 
If you want it as a backup for when someone forgets the action, then something longer about a second is fine – the aim is to be there only if the user has that moment doubt.
 
However, I was fascinated by how long the delay needed to be to feel ‘instant’ and yet not appear by accident.
 
For me about 150 ms is not noticeable as a delay, whereas 200ms I can start to notice – not an annoying delay, but a very slight sense of lack of responsiveness.