Stephen King: He wrote a story about a person that was so obsessed with minimizing the driving distance when going places that he ended up finding 'dark and shadowy' paths that got him there faster than reality would allow. The trade off is that he started getting younger and younger, probably inevitably.

Mage: Creating fireballs and lightning bolts out of your hands as a modern-day mage is frowned upon by reality. Reality fights back with "Paradox", the collective unbelief in magic causes you pain when you do 'vulgar' magic. You shoot a lightning bolt out of your hand and reality breaks your arm to compensate. So you do your spells in 'coincidental' ways. Instead of a lightning bolt you cause a nearby transformer to overload at just the right time.
So to cast a spell that will guarantee a safe/quick/whatever trip, you must go very much out of your way. Or something.

I didn't say it would make sense. My mind is twisty and confusing.