From one of the earliest posts on this thread - it's been suggested local weather was worse than forecast and after 3 failed attempts to make progress (to a site less than 20 miles away) a low ground route and a break in the weather allowed progress to be made. The forecast is but a planning aid, if you encounter worse then rework the plan. If I diverted or picked a field due to unexpected nasty low clag, then I'd need a significant sustained improvement to warrant an attempt to continue VFR/VMC. So why do we try multiple attempts in the hope of finding a lucky gap?
This was me. I was in a Super Cub within ten miles of home and I know this local area intimately. The clag does often hang on the high ground between me and my destination. I went up for a couple of looks above the strip I had gone into and it wasn't quite nice enough to go on, but not absolutely dire. I then headed South around the low ground and it was actually fine with never less than five miles vis all around, but obviously to the West and North it was a lot worse, which was not an unexpected finding. Knowing the area, if anyone had suggested to me on that day at that time that I should continue towards Bude I would have laughed at them. At all times I had a variety of options (not least Dunkeswell clear behind with a 1500 ft cloud base) and intimate local knowledge with up to the second on the ground weather reports texted from pilots in three different locations on my route.
Every situation is unique, but what is important is to have a plan with options and to use the options at the right time, not just press on into deteriorating conditions with no 'out'. That's judgement.