Gaynor Redvers-Mutton of the Biochemical Society, in an interview with Scholastica on the Society’s disastrous dalliance with APCs:

Commercially, the rationale inbuilt to the APC-funded model of OA publishing is to out publish everyone else to scale your operations to publish research faster and more furiously than others. Basically, to win market share — the more you publish, the more you earn. As a not-for-profit publisher, we don’t have that commercial imperative, but for other reasons, we have had a glimpse into what this type of publishing looks like and have been burnt by it.

The Society had flipped one of their journals to APC-based OA, back in 2012. By 2019, they were having doubts:

The wholesale move to an author-pays model didn’t stand up to the Society’s collective view that the ‘ability to publish should not be linked with an individual researcher’s ability to pay.’ Article publishing charge-based open access models that removed the barrier to reading replaced it with a new barrier to publishing and therefore ran contrary to prevailing views.

That year, and into 2020, the Society was targeted by bad actors:

And then our sound science, APC-funded journal became our achilles heel. We were an early target of papermill activity, and just as this blight hit us several years ago, it has now spread sector wide.

The whole interview is worth reading.