One thing that grinds my gears is motorcycle batteries.
No matter what kind of tender loving care you give them over the winter they always seem to let you down. You can tend them monthly over the winter months keeping them in a cool dry place and sending a small trickle charge into them to keep them topped up and fresh. But in the spring when you need them they are dead as a doorknob.
On the other hand friends who put their bike away for for the winter with nary a thought to their battery, dig them out in the spring and after a quick charge are on their way.
Seems like the meaner and nastier that you treat them the better they work.
Batteries!, you can't live with them and you can't ride without them.
Looks like I am going shopping.