I've already used "purpose" a lot, in a different context, and I need
to avoid using purpose for this statement to prevent confusion.
This architecture has exceeded it's original raison d'être and needs major refactoring.
Raison d'être, raison d'être (n.)
Reason or justification for existence M-W
A reason or purpose for the existence of a person or thing [OED]
(Dictionaries and style guides differ on italicization.)
The raison d'être and the challenge of symbolic languages are to
construct highly sophisticated software which would be too complicated
or unmanageable if written in other languages. A.C. Kakas and F.
Sadri; Computation Logic (2003)
First of all, since the whole point of having such an institution is
to secure, in the best way possible, the enjoyment of fundamental
rights, a legislature that compromises those rights without a morally
acceptable trade in security will exceed its justificatory bounds
and lose its raison d'être. John Kleinig; Ends and Means in
One of the objectives was to give inventors' certificates the same
status in the Paris Convention as have patents in that Convention.
With the abolition—shortly before the Soviet Union ceased to
exist—of inventors' certificates in that country, this objective of
the planned revision lost its raison d'être. WIPO and A. Bogsch;
The First Twenty Five years of the World Intellectual Property Organization (1992)
Knowledge of the substantive solutions reached by the courts of each
country cannot be sufficient. To conduct his comparison work, he needs
to know the spirit and the raison d'être of each solution.
Eduoard Lambert (1900) in E. Lees and J. Viñuales; Oxford Handbook
of Comparative Environmental Law (2019)