When you do an update on your wizzle, at the very bottom the date should change - it should say "Updated: --/--/----"
This is important because the date gets displayed in the SERPS and seems to increase clickthrough rate.
The following article also shows a case study where just the date changing appears to have increased search engine rankings, because Google favors freshness:
https://moz.com/ugc/case-study-can-you-fake-blog-post-freshness-
It's compelling enough to make it worth while to go through wizzles correcting spelling mistakes, improving product selection, updating information, anything that will allow you to update the page and hence generate an updated date.