[The following reflection was prompted by a discussion in the Aeclectic Tarot Forum. It's not meant to be conclusive.]
Some people say that divination is about, as the name says, purely "connecting with the divine" in order to gain information.
I feel unsure about this definition, because many times in my life I have struggled to trust in a all-seeing and ever wise "divine", such as Guides, Angels, Deities, Spirits, or a Higher Self etc. I prefer to think that everything around us is divine because... well, it is all there is, isn't it? It's the grand mystery of which we are a part, but that none of us can fully understand, envision or explain. But I can't decide yet whether I believe that there is a greater intelligence guiding our steps or not.
That said, I do think divination is like having a map.
Reading the map will show you what to expect in your path, which way is better, which one is easier, which one is more difficult... It'll help you plan ahead. But it'll not show you every bump on the road, every dangerous curve, every choice you'll need to make. And it'll not show you your whole path - a map, after all, is just the limited snapshot of one single moment in space and time.
Some people spend too much time reading the signs, but do not enjoy the trip.
Divination, in my opinion, is best used when it helps you to make informed changes and decisions. And also, when it gives you the chance to ask yourself why you are chosing one path and not the other, thus making you more conscious of your own inner and outer processes.
It's not meant to replace life. It's not meant to protect you from it. The future shown in the cards is not meant to replace the present - it's meant to help you to understand what you are creating now.
Ultimately, the present is the only time that ever really matters.