Generally not, at the time of cleaning.
because you should have removed all the dirt on the frame and glass,
the rain is almost as pure as your pure water, in most of the country,
On a maintenance clean - the windosw are generally still clean after 4 weeks,
you are removing the small build up of dirt, dust, grime, insect crap and bird mess that has taken 4 weeks to accumulate
But some customers will still not understand, better off without them - let somebody else pander to them