If I’ve been thinking about a specific wine all week (as @danchaq says so evocatively, “whispering to me for days”) then I’ll plan the meal around it. But mostly the big influencers are: what’s the day of the week (normal working day, weekend, or holiday?); is anybody coming to dinner?; are we eating something normal or something special; and what’s the time of year/season/weather like? These tend to lead to a wine and a meal.
Sometimes it’s more spontaneous - even wines that I’ve been cellaring for years and years can sometimes, without planning, make an appearance because the right guest is with us, the conversation is great, the food just demands it, or the wine we’ve just had needs to be compared with something similar but better, and the wine is given a chance to make a star appearance.
Spontaneity is great, and we shouldn’t be afraid of letting it happen, even with our best wines. The more you fetishise a future occasion, the more you’ll agonise over the wines, and the greater the risk of disappointment.
Uncork with confidence! As they say…