I agree this is likely wrong assumption.
The problem assumes by itself that less time = more mistakes.
Option A is far better it states that less money is available to train and thus more mistakes are likely.
This questions is dubious version of
When demand for a factory's products is high, more money is spent at the factory for safety precautions and machinery maintenance than when demand is low. Thus the average number of on-the-job accidents per employee each month should be lower during periods when demand is high than when demand is low and less money is available for safety precautions and machinery maintenance.
Which of the following, if true about a factory when demand for its products is high, casts the most serious doubt on the conclusion drawn above?
(A) Its employees ask for higher wages than they do at other times.
(B) Its management hires new workers but lacks the time to train them properly.
(C) Its employees are less likely to lose their jobs than they are at other times.
(D) Its management sponsors a monthly safety award for each division in the factory.
(E) Its old machinery is replaced with modern, automated models.
The answer for the above is far more reasonable and conclusive.
Who so ever is making these wrong versions need to stop ,because they are just lowering others' morale by giving inconclusive justification to their wrong versions.
The Original one is far more superior.