Why? Because it is an aggregate noun. So what? The word aggregate refers to a “whole formed by combining several elements that are typically disparate,” i.e., elements that are different in kind. (I’d like to think of these elements as “hiwalayable.” :D)
In grammar, an aggregate noun is a single collection made up of individual parts. It is plural because each part is considered distinct, separable and equally significant. Unlike a collective noun, an aggregate noun cannot be used with a or an and often uses a plural form.
Examples: With the development of the Internet, communications are being revolutionized at a dizzying speed. The headquarters are ready for the chief’s retirement. Congratulations are in order. The stairs need repairs.
I think that the word minutes collects all the minutes spent at the meeting but considers each minute significant and separable, hence, the collection is treated as plural.
Some aggregate nouns are singular in form but still use plural verbs.
Examples: The police are still looking for the Olympic Park bomber. The people are excited about the upcoming concert. The clergy were ready for the TV crew.
Some aggregate nouns can use either singular or plural verb forms.
Examples: The data [is/are] inconclusive on that point. (Note: Modern usage often treats data as singular.)
The laity [has/have] played an important role in the history of the church.
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