Most sales tend to start the week of Black Friday and continue through the weekend to the following week
What used to simply be “Cyber Monday” (the Monday after Thanksgiving) has now morphed into “Cyber Week.”
But the idea that we should scramble to hastily amass discounted products on "black friday" is absurd
and same goes for "new years day sales"
more about “derivatives”
Motley Fool exposes this practice around high-end TVs
https://www.fool.com/investing/general/2015/11/26/dont-buy-a-tv-on-black-friday.aspx
also Sidenote:
some codes to watch out for on sale prices
example: Next codes, you'll see these on the price tags in shop, are like this > B14, G4, P7, OB9 and S13.
more here:
The reason Black Friday exists is to bring you in with the really cheap, rock-bottom prices in the hopes that you do jump on those filler deals while you’re there.
Being really aware of that and trying to avoid that temptation is important