I think that quote is much too broad with the modifier "might." If you should procrastinate based on a possibility of improved odds, I doubt you would ever do anything. At least a reasonable degree of probability should be required.

Not to mention that the natural inclination of most people toward procrastination means that they should be distrustful of feelings that delaying will be beneficial; it's entirely likely that they are misjudging how likely the improvement really is.

That's not, of course, to say that we should always do everything as soon as possible, but I think that to the extent that we read the plain meaning from this quote, it's significantly over-broad and not particularly helpful.