Recently we’ve moved a customers website into a child theme, why you may ask?
The original developers had customised a purchased theme by changing core templates, this in itself may not be so bad but the website owner was unable to update that theme for fear of losing the customisations and possibly/definitely breaking the site.
We were able to setup a development site for the website owner, then update the theme and create a child theme from the newly updated theme. We integrated the customisations from the old template files into the new child theme and migrated the updated website back into the production website.
Our customer can now safely update the parent theme files whenever updates become available without fear of breaking the website, the website owner can also take advantage of security updates, improved code i.e performance and any additional features that the theme developers have introduced.