When to abort, written before you launch
An abort decision made on the water is usually late.
Declare the trigger
Write three triggers on the deck card: a latest decision time, an observed sea state, and a wind reading. When any one of them is reached, the leg ends. Three is enough to be remembered and few enough to be honest.
Name the exit
The trigger is useless without a landing named next to it. Name the exit before launch and check it at low water, so the abort is a route rather than a search.
Remove the negotiation
The most expensive minutes of a marginal leg are spent discussing whether the trigger really applies. Decide before launch that a trigger is self-executing; it does not need a second opinion.
Log it
Record the abort and the trigger in the log. Two lines make the plan reviewable next season, and a reviewed plan is the only one that improves.