I really dont have any answers about persons not having many bees...maybe ck for a queen or brood again when there is a good day. Perhaps some of the bees did not make it thru the winter, but these did? are there mites that could have reduced the population? I always have more questions than answers myself.
I lost a hive to mites last fall- I dont treat with pesticides and this year I will try cultural methods. I also lost a strong hive this winter. They were dead, all balled up between frames, plenty of honey in the hive. I have no idea what got them.
I have one hive left which seems to be going strong. I opened it up this weekend and "flipped the supers" - top one to bottom, bottom one to top. There were plenty of bees. I lightly smoked the hive, but I guess not enough, and was driven off, which happens to me a lot. Anyway, I did pull frames, saw brood, but never got through the whole thing before bees got inside my veil and, well, tried to make a pin cushion out of my face. I was lucky to get the whole hive back together!
At bee meeting they say it is best to have more than one hive so that you can compare how they are doing. Interesting that in my yard, 2 die of different causes, while one colony grew stronger...