In some cases, the hunt for performance indicators (and a higher impact factor) has become the main priority at the expense of the actual scientific work. The need to survive, the need to achieve good performance indicators and the need to receive funding sometimes result in unacceptable publishing behaviour. Excessive personal ambition can contribute to this behaviour, too.
Predatory publishing is only one aspect of the problem. There are other ways that standards are being bypassed. Failure in the peer-review system is not unusual, for instance. Peer-reviewing in some ‘good’ journals is lapsing into clientelism, cronyism, camaraderie, false collegiality etc. The quality guarantors of ‘good’ journals used to be second-class scientists who became ‘editors’ who often placed more emphasis on form than content.
‘Publish or perish’ together with market demand and supply in the absence of morals and ethics have a ‘carcinogenic’ effect and they infest and infect the scholarly community.