Well I am all sleuthed out. I have over 60 chickens, admittedly over half of them chicks less than a month old. At least 5 of our chooks, however, full-fledged "hens", and we only get 0-2 eggs a day. My barred rock never laid until she was 35 weeks, finally started laying at Christmastime (even though she hatched more than 8 months earlier), then she only laid eggs until April of this year, then just stopped. Now she acts like an old hen and just hangs out in the yard. The rooster doesn't mate her & she doesn't lay eggs. She is barely over a year old, and we have not had an egg from her in about 6 weeks. Since April, we have had a grand total of 2 eggs from her. She's not molting. I got her as a young pullet from a questionable chickenkeeper, though, and of the 5 pullets I bought from this person, only the barred rock (that doesn't lay) and 1 Easter egger are still alive. The rest are all dead, none of them accidental--all from various health concerns. I still have no idea why my barred rock stopped laying.
I have one hen that went broody a while back & now has 8 chicks that she's raising/mothering. She will be a year old on July 13th, and this is already her second brood of chicks (she started laying in January, went broody 4 weeks later). I have one other hen that just went broody this past week. That leaves Lola (my red/brown ameraucana) and Bertha (my black and gold EE). They're the only ones laying right now.
I originally went into chickenkeeping to get eggs, but I had bought my chickens as young pullets of about 8 weeks of age. Of those 5, two never did lay eggs, and like I said, the barred rock only laid for 4 months and then just very unceremoniously stopped laying. She also does not hang out with the other hens anymore and is kinda a loner. She sits by the back door and stares at me and wants to come in.
It is a good thing I fell in love with my chickens and am not depending on them to provide eggs to feed my family, because I have not had much luck with egg production from my flock.
I think sometimes, they just stop laying for unexplained reasons.