Why does the brake fluid need changing in my Peugeot 407 SW?

I have owned a Peugeot 407 HDI 140 SW for four years and I thoroughly enjoy the car. Servicing has always been done by the excellent local Peugeot agent. I took it in today for 50,000 interim service; told a brake fluid change "has never been done and is overdue". I queried "has never been done" because it has never been mentioned to me at any previous service. The agent said "It's not our habit not to mention things like that". I replied "It's not my habit to refuse." It was all very good-natured, and if it is necessary of course I'll have it done, but if it's overdue, why haven't they mentioned it before?
Brake fluid can be tested for contamination and moisture content and only needs to be replaced if showing undesirable amounts of these.
Answered by Honest John on

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