It sounds like the article is referring to manufacturing. With manufacturing vocabulary, "lot" is the same as "group" or "batch". For example, if a factory manufactured 100 computer chips at the same time, the following four phrases have the same meaning:
"The lot size was 100."
"The size of the lot was 100."
"The size of the group was 100."
"The size of the batch was 100."
Those 100 computer chips will probably all have the same characteristics. If the manufacturing process was defective, then maybe all 100 computer chips would be garbage. That's a waste of money!
Instead, if you manufacture only one computer chip at a time, the lot size would be one. If the manufacturing process was defective, then only that one computer chip would be garbage. Or maybe that one computer chip could have special characteristics that the customer requested. The article you read might have a better explanation of the benefits of this approach and also how the newest technology will affect it.