Answer & Explanation :
Hypothesis Testing is used to check statistical significance of mathematical propositions. Null Hypothesis is a neutral, no difference stating hypothesis. Alternate Hypothesis is the hypothesis stating particular difference.
To study that 'compensation plan increases or not the average sales per salesperson'
Type 1 Error is rejection of an actually true null hypothesis. In this case, it implies that compensation plan is concluded to impact in higher sales, when actually it has no impact on sales. The consequences might be that, the plan will be implemented because of the mis-conclusion. It might not be really useful in increasing sales thereafter.