Markku Laakso used to have an article. This Mr Laakso was actually a conductor and not the diabetes researcher the list was there for. For whatever reason, the article for the conductor was deemed to be not notable and it was deleted.
When you are NOT a Wikipedia admin, there is no way to know what was deleted.
One solution is for all blue, red and black links to refer to Wikidata items. When an article is deleted, the Wikidata item is still there making it easy to prevent cases of mistaken identity like with Mr and Mr Laakso.
A more expanded proposal you may find here.