Henri Nouwen called solitude..."the furnace of transformation." This doesn't refer to mere personal privacy for a twelve-second pit stop where we get a quick fix to reenter the race.
It's more than that.
It's an oasis of the soul where we see ourselves, others, and especially our God in new ways. It's where much of the "clutter" of life is identified and exterminated, thanks to the merciless heat of the "furnace."
Soul surgery transpires as serenity replaces anxiety. In solitude, struggles occur that no one else knows about. Inner battles are fought here that seldom become fodder for sermons or illustrations for books. God, who proves our deepest thought during protracted segments of solitude, opens our eyes to things that need attention. It is here He makes us aware of those things we try to hide from others.