I know people who went to the airport with no idea where they would be flying to. That is not me.
A lot of what we do requires planning.
If you are going wilderness canoeing/camping finding out after someone broke their finger that one has forgotten the first aid kit is not acceptable. Especially in the north american Rockies, Prairies, in August one can have scorching weather, we have also woken up in August with 20 cm of snow on the ground that was not forecast. So basically one has top be prepared for everything. Many people consider wilderness camping to be light weight camping, you are actually preparing all eventualities. The wilderness canoes are designed for this. Empty, with just two people, they sit too high in the water, and are quite tipsy. Loaded up they are snuggly in the water.
Sailing, especially if you are travelling between countries, oh boy, you better plan.
Just the customs and immigration part.... Some countries want you you to inform them when you are leaving port in the previous country, others want to be informed just 48 hours before arrival, others 24. Some countries just want you to deal with the local harbor master, and he will facilitate everything, others want every email to be CCd to the head of immigration. Some countries want everyone to leave the boat and head to immigration, others want just the skipper to leave the boat with everyone passports, the others stay on board. With others still, custom and immigration comes to you. Some want a list of every persons personal electric devices to be listed. Others want every data processing device installed on the boat to be listed with serial numbers, including engine control units. There are over 50. Some accept it if everything is digital, others demand everything to be printed. Bad time to figure out that the printer will not print, or that you do not even have one on board. Some consider documents voided if there is any markings on them, others want the skippers signature on everything, others want no signatures but the yachts registered signet stamp on all docs.
Mess anything up, and you are potentially facing thousands in fines, and even jail time. Yeah, you need to plan.