Been buying and selling on eBay since 1997 and made an observation verified by other long-time auction users (as seen on message boards for big-time on-line auction sellers)........
Things slow down in the summer then pick up as fall arrives. Likely due to people being outside more and away from the computer in the summer. Also, possibility of costs of vacationing reducing discretionary income.
Many sellers either slow down their sales or stop entirely during the June-August period then start relisting again in September.
For the best bargains, summer tends to be a buyer's market with fewer bids for items. It's just a tendency since some items are highly desireable with a dedicated group of buyers regularly checking to see if the object of their lust is available.
I wonder if Nichole Kidman will ever be on eBay. I'd bid on that!!!!!