Miserable people who try to keep conditions so miserable that no normal person would want to take the job. It has to do with hazing & job security for anti-socials is what I figured. I once had a QHSE lady who came on a tug that I worked & gave a long spill about fatigue & a study performed by the USCG about dogging the watch being the best schedule for a 2 man rotation. It consisted of two people working 8 on, 4 off, then 8 off then 4 on. We only had a 2 person E/R & my assistant & I wanted to give it a try. The anti social, wacko captain that we worked with went into a screaming frenzy at the idea of his crew working anything other than 6 & 6. It would have only been me & one other guy willingly trying it out but the plan was dead on arrival from the disgruntle skipper. Too many tug people hate everything but what most hate more than anything else is change.
That being said, I didn’t mind the 6 & 6, 12 & 12, days only, nights only or the 4 & 8. What I probably dislike the most of all is the 8 & 16. I couldn’t imagine working any of those schedules for 20 years straight & enjoy the idea that I can change it up every few years if I want to take on a new adventure somewhere. If a person doesn’t want to work 6 & 6 then don’t.