Are internal gutters problematic?

Dear forum,

we are currently planning our new building with internal downpipes. These were planned by our architect at four points in the external insulation. We recently had a conversation with our roofer. He had little experience with this, but still pointed out the risk that moisture could penetrate the masonry unnoticed in case of material defects. What are your experiences and assessments here?

I ask myself: Why does one do that? For aesthetic reasons?

It wouldn't be for me. I'm already worried about my house with the connections for the shower/bathtub ;)

Yes, for aesthetic reasons we are currently planning it that way. It would be interesting to know whether this constitutes a serious risk.

Yes, leaking downpipes always exist. Therefore, I would not install them in the insulation. There are better highlights for the appearance than these construction blunders.

Frankly, I also suspect technical reasons for the extreme short-lived nature of this fashion, which to my recollection lasted no more than two years around 1980.

Stupid idea …… leaking then you have to open up the wall