A problem with the term "end-of-day" is that it has been widely used by dealers and collectors to apply to any glassware that does not seem to be of "very good" quality! For example, regular 19th century production Bohemian spattered glass is so often called "end-of-day" - just because the decoration consists of simple patches of colour over clear. And the same sort of generalisation has been applied to some paperweights, which, as I indicated earlier for Perthishire & Murano scrambled weights, are actually regular production items.
I believe it is a mistaken notion that at glassworks the pot (or tank?) would be emptied at the end of each day by workers "doing their own thing" and creating personal (gift or "beer money") items. Personal items (friggers) have always been made, but not in the quantities that are so regularly available.
In major glassworks, the glass batch would last for about a week. In smaller works, the pot would probably be topped up several times over many days, rather than "use up, then refresh" every day. I am happy to be challenged on this by any glassworker who happens to be reading - and I would welcome their comments on whether "end-of-day" really is something that occurs.
So, I disagree with the all too often use of "end-of-day" (or perhaps "end-of-week"??) for many items that were most likely just a "more affordable" range but made as part of the regular production output. But it is a term that maybe all of us pick up on it when we first get into glass collecting. After all, it is so often seen in books as well as heard at fairs and auctions.
And, by the way, it's not just me saying this ... in British Glass 1800-1914
, page 308, Charles R. Hajdamach wrote:
The term 'End of Day' glass has become commonplace in the antiques trade for most of the spangled or mottled glasses. This suggestion that they were made at the end of the working day to use up the unwanted glass is erroneous and the large number of patents for the style proves that it was a commercial line with a great number of of competitors.