An itinerary fails on transitions, not on activities

Itineraries are written as a list of things to see. They break in the gaps between those things, which is where every dependency and every delay accumulates.

Activities are self-contained and transitions are not

Visiting a place has a defined start, a defined end and few dependencies. It rarely overruns in ways that affect anything else.

A transition depends on a departure time, a connection, a route, and often on a check-in or a key collection at the other end, each of which can fail independently.

Because the failures are serial, the probability that a chain of transitions completes as planned falls quickly as the number of moves increases.

Luggage is only a problem in transit

Bags are irrelevant while at accommodation and dominant while moving. A transition day is therefore a different kind of day, with worse mobility and fewer options.

This is why a change of city consumes more of a day than the journey time suggests, since the hours either side are constrained by having a bag to manage.

Left luggage restores those hours and is usually available at stations and through the accommodation at either end, which converts a wasted afternoon into a usable one.

Check-in and check-out set the shape of the day

Accommodation releases rooms in the afternoon and requires them back in the morning, so a transition day begins with a deadline and ends with a wait.

Building the day around those two fixed points, rather than around what there is to see, produces a plan that survives contact with a delayed train.

Where a property has no staffed reception, the arrival window narrows further, since a key collection with a defined time is a harder constraint than a desk that is always open.

Fewer bases is usually the answer

Three nights in one place with day trips generally sees more than three single nights in three places, because two transitions have been removed from the plan.

Day trips also return to a known room with the luggage already in it, which removes the arrival problem that makes each new place cost half a day.

Where slack should be placed

Buffer time is worth most immediately before something unrepeatable: a flight, a booked tour, a ferry that runs twice a day. It is worth little between two flexible activities.

Concentrating the slack at those points rather than spreading it evenly means the plan absorbs delays where they matter and stays dense where they do not.