In the marinas you have limited maneuvering space and with sails you are limited in which directions you can go - directly against the wind is not possible, you need to zig-zag. Slowing is also a bit more difficult. To add to trouble, marines are often built in places with less wind (of course) and wind might change direction during landing. Note that it's still quite possible, just more challenging, risky too I guess, and also forbidden in many marines. But it's a good exercise, it makes one respect ancient mariners even more.

Extending this comment, before motors it was routine to have to wait for favourable winds, especially in harbours and confined waterways. Here's the famous navigator James Cook setting out from London on his second voyage:

"I sailed from Deptford, April 9th, 1772, but got no farther than Woolwich, where I was detained by easterly winds till the 23d, when the ship fell down to Long Reach, and the next day was joined by the Adventure. Here both ships received on board their powder, guns, gunners' stores, and marines."

[http://gutenberg.net.au/ebooks/e00044.html]

So the "Resolution" managed about 8km on the day of departure from the London naval dockyard, then remained anchored in the river for 13 days waiting for the wind to change direction, finally managing 16km to the victualling dock.

I've read about the "waiting for favorable winds" in novels and non-fiction before but I've never connected it with mooring. Thanks!

Thanks for the explanation, appreciate it!