
they had to bring their own harbours because the existing ones wwere both well defended and mined. To avoid that theyd have had to make tthe primary invasion through southern france or the balkans.
They were probably going to have to do that no matter where they landed. Dieppe had shown the folley of directly attacking a defended harbor and all of the ports along the occupied coast of northern Europe had some kind of German garrison.
No, Normandy wasn't the worse location they could have landed at. There were other locations that were almost identical to Normandy in terms of their beach make-up... except they were outside the range of Allied (land-based) tactical airpower.
One of the worst. Not "the worst".
And I know that they had (heavier than Normandy) defenses, thus the whole "except for considerations like why the Allies felt it was worth it." - normally, one does NOT invade when one has to bring one's harbors with you, which is why the Germans expected the Allies to regard needing a harbor as an overriding concern instead of suspecting the Allies would have something like the Mulberries, which were an extremely clever - but not exactly inconceivable - solution.
If I was Ike, the better part of the reason for picking Normandy is not that its a good location to having to land and supply an army from but that the good locations are too tough to crack (at a reasonable price in men/materials/time).
Which is not to fault the decision - as stated, I think the Allied planners made the best choice of their available options, with the benefit of seeing how they went about dealing with the reasons against Normandy (very, very effectively).