I know that you don't have to update wills as long as you don't want to change the intentions, but really, executing my dad's 50 year old will was a pain! Like bothering an elderly lady I didn't know for the date of her husband's death so I could get a certificate as he was a named executor (why? I couldn't remember who he was!). I was lucky she was still alive (almost 100) and living in the same house!
My late FiL did a DIY will that he updated every 3 years, and his was easy to follow and execute.
I don't advocate them, I just think there are times they fit the bill. We needed to change our wills, short of both time and money, so we did a DIY - sell the house, entire estate divided evenly between our adult children (no steps, adopted or complications). Two years later when all was settled we saw a solicitor for the full proper works.