I’m not a crane person, but I am familiar with the term duty cycling. In a lot of critical applications, you will have two motors available to be used, so that if the first motor fails, the second one can be used. In order to keep both motors healthy and operating, you’re supposed to switch off duty between the two motors on a fairly regular basis. This keeps both motors at about the same operating age, and avoids the problem of having your backup motor unable to start because it has seized up because it has been idle too long.
Also, as an aside, according to the instructor for the OSHA safety class I took a couple of weeks ago, your timing is impeccable. OSHA is about to put in place some new rules that require the CCO certification you’re speaking of. In his opinion, there are a lot of people out there right now who are excellent crane operators who will be freaked out by the complicated test, and a lot of people who will ace the written exam, but don’t have the practical experience to operate the cranes all that well. He projects that those who can do both and get their certification in soon will be able to write their own ticket for a while until the supply of certified crane operators increases to meed the demand.