Interesting question. I "inspect" my hives every time I am go to a bee yard which is about once a week. That being said, other then in the spring when we are splitting, re-queening and monitoring the progress of splits my inspection consists of looking at the front entrance and popping the lid. I usually won't tear into a hive unless something looks out of place. ie - the hive is noticeably weaker then those around it. Once supers are on I just monitor the rate at which they are filling. If one is again noticeably behind the others I may dig further to find out what's up with it.
On re queening I place the queen and return in a week to see if she is released. If she is not I usually release her. I then return in a week and check for eggs if they are there I look no further. If I can't find eggs, I look for the queen. If I can't find her I mark the hive and return in another week. By this time if there are no eggs and no queen I re queen or usually just nuc the hive by placing the nuc frames on the bottom, newspaper and then the old hive up top. So far have had 100 acceptance using this method.
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