Conversation so far:
when is the danish/swedish crime drama the bridge series 4 on bbc 2?
There are no upcoming broadcasts of The Bridge.
can I watch Danish/Swedish crime drama The Bridge Series 4 on BBC iPlayer?
The series is not available on BBC iPlayer.
was the Danish/Swedish crime drama The Bridge cancelled?
When the fourth series started broadcasting on 1 January 2018 in the Nordic countries, Rosenfeld confirmed that this is the final series.

Question: what was the reason?
Self-contained rewrite: what was the reason for the Danish/Swedish crime drama The Bridge being cancelled?