"The most recent case was in 2018, when Changsheng Biotechnology Co. came under investigation for falsifying records and making ineffective rabies vaccines for children.

In 2017, Wuhan Institute of Biological Products Co., a CNBG subsidiary behind one of the vaccines in phase 3 trials, was found to have made defective diphtheria vaccines that were ineffective."

The financial incentive for just getting something out there, anything, is massive. If it doesn't work then later we can say:

'In the battle against an evolving, unprecedented virus, vaccine development is not an exact science, it's an ongoing process.'

The message will be - that one didn't work - but how about trying this new one!?