decision making one pilots model .. weather.
Before departure, is the destination (and alternate) within forecast weather limits at the proposed time of arrival ? answer yes .. despatch.
Answer no ? when are the conditions forecast to improve .. consider delay.
Destination out of limits, alternate (and now a second alternate) OK, depart and check weather en route for destination, still below limits continue to alternate no approach.
Destination within limits before final approach fix WITH NO APPARENT SEVERE WEATHER HAZARD OBSERVED, an approach may be made initially to FAF, if still within limits, continue (maybe) to minima.. land/go around as appropriate to the conditions, if go-around, check fuel/scare factor and divert.
The critical factor is "extra" fuel, that is your thinking time.
Something else worth considering is planning to your "1st alternate" and making the original destination an alternate.
Had an experience where destination was forecast to be unusable due high winds, checked the weather en-route and it was as forecast, decided to divert at top of descent, 1st alternate not available due lack of ramp space (all the other diversions) second alternate likewise !!... third alternate was fine though.
food for thought at least.