PMY - Power&Motoryacht

I see pictures of many big yachts with a dozen or more underwater lights.
To install them requires drilling the hull. Does that present - in time - a possible leakage problem?

Does installing near -waterline portholes/windows increase the chances for water leaks of a minor or major type in time? In heavy seas with possible rogue waves I would think a wave hitting the sides would do more damage to glass or lexan portholes than a multi inch thick hull.

Can anyone illuminate me on this??

Jack
Pinellas Park, Florida