INDAS 23 capitalisation rate

HARDIK (Student) (42 Points)

15 October 2019  
IND AS 23 says that

The average carrying amount of the asset during a period, including borrowing
costs previously capitalised, is normally a reasonable approximation of the
expenditures to which the capitalisation rate is applied in that period.

then what is logic behind applying rate on amount which includes previous year's capitalised borrowing cost ( though it is already paid)