Skepticism is about the truth. But there's more to it than just truth. Everybody is interested in the truth, after all. So what makes skepticism any different? What else does it value?
If you said "evidence", you're correct. But I view things more broadly. People are rather fond of saying that not everything is about cold hard evidence. I agree. In most areas of life, you will never be able to provide cold hard evidence, nor create overarching theories that explain broad swaths of phenomena. But I still think there is an evidence analogue in the fuzzier parts of life. While we do not care about cold hard evidence, we should still care about why things are true.
The first natural question is "Why ask why?" In science, we care about the why for several reasons. In science, we want to be able to convince other people. But in the rest of life, it's not our primary purpose to tell other people how to live. In science, we want to understand the underlying mechanisms so that you can predict other things too. But in the rest of life, underlying mechanisms, if they exist at all, are far too complicated to discern.
Lastly, in science, you want to know what would be needed to falsify your theory. This last reason is valid in the rest of life too. After all, anything you say about life in general is bound to be wrong some of the time. If we know why it is correct, we will have a much better idea of when it is incorrect.
Let's take an illustrative example: "Eat, drink, and be merry, for tomorrow we die." With slightly humorous intent, I will take this statement literally, and ignore its original context.
This little "truth" says we should eat, drink, and be merry. Why? Because tomorrow we die. Well, like all things, this truth is uncertain. There are at least some instances when it is wrong to eat, drink, and be merry. When is it wrong? Well, it might be wrong if tomorrow we don't die. If that is the case, perhaps we can find another reason to eat, drink, and be merry. Perhaps you should eat, drink and be merry because you enjoy doing so. Or maybe you can't find a reason, and should starve.
And another example: "A spoonful of sugar helps the medicine go down."
Why does a spoonful of sugar help the medicine go down? Because the medicine is good for you in the long run, but tastes gross by itself. Therefore, this wisdom does not apply when the medicine is not good for you in the long run. Nor does it apply when the medicine already tastes good by itself, or when you have no sugar to spare. The same reasoning still applies when the expression is taken metaphorically.
Sometimes it rather bothers me when I hear people simply quoting something clever without any hint of why it might be true. I mean, do people really think that there's anything in life that's true all the time without exceptions? For instance, consider the values of "open-mindedness", "diversity", or "moderation". Not to say these things aren't good, but it is nevertheless important to know why they are good, and thus when they are good.
If I may indulge myself with a statistical metaphor... not saying why something is true is like not reporting error bars.
And it's not even like it's hard to come up with reasons for these things. You don't need to write a dissertation about it or anything. Just a little something like "Be open-minded, for you just might be wrong". Easy. And you'll get better insight into the vagaries of life this way.