Both the Saturn V and the Falcon 9 use TEA-TEB to ignite their kerosene-fueled engines. TEA-TEB is pyrophoric, igniting spontaneously on contact with air. This poses handling issues; it must be stored in nitrogen.
It's also an expendable resource which puts limits on the number of times an engine can be started in flight; the Falcon 9 only loads TEA-TEB for restarts on those engines that will be restarted on a given mission, reasonably enough, but this makes it susceptible to engine failures in the reentry and landing burns that could otherwise be recovered from by using different engines.
Some other engines, such as the hydrogen-fueled J-2 and RL-10, use electric spark ignition rather than a chemical starter. Both engines are reliable and capable of multiple restarts after launch.
Can kerosene-LOX engines use electric ignition? If so, why consider a volume-limited and hazardous chemical igniter like TEA-TEB?