When does a button hold "too many" words?
Background
I came to ponder this question whilst mocking up a modal window for the application we're developing. I had trouble summarizing the semantic phrase: "Click here to get a list of all of the subscriptions this pool contains". I created a button saying "Show subscriptions in pool", and thought to myself that this can't be right...
When phrasing button text the best practice should of course be to as clearly and as briefly as possible describe the effect of the action, "less is more" really comes into play here.
I guess you could compile a chart for how the text of a button should be composed, if the situation allows for it of course:
- One word : Ideal
- Two words : OK
- Three words : hmmm...
- More words? : =(
(Please note that this estimation is done purely from my own reasoning, I have no reference to back it up with)
Question
I would like to know if there are any studies conducted with this question in focus? Or if you know of any heuristics that would suggest a threshold, usability wise, for how many words a button can hold before it would be considered to be "too much"?