No matter how many detours and adjustments it made, the caravan moved towards the oasis.

"The desert was all sand in some stretches, and rocky in others. When the caravan was blocked by a boulder, it had to go around it; if there was a large rocky area, they had to make a major detour. If the sand was too fine for the animal's hooves, they sought a way where the sand was more substantial... If a guide were to fall ill or die, the camel driver would draw lots and appoint a new one. But all this happened for one basic reason: no matter how many detours and adjustments it made, the caravan moved towards the same compass point. Once obstacles were overcome, it returned to its course, sighting on a star that indicated the location of the oasis." - The Alchemist by Paulo Coelho