... competitor. Rejecting the null hypothesis with α = 0.01 protects you from overreacting to the claims of the analyst.
Why not require α to be smaller than 0.05 all the time? We could, but doing so increases the chance for the other error. The smaller one makes the α-level, the greater the chance for a Type II error. 
Small values of α make it hard to reject the null hypothesis, even when it is false and should be rejected.
To make it easy for individuals to use their own α-level, statistical software commonly reports the p-value of a test. The p-value is the smallest α-level at which the null hypothesis H0 can be rejected. (The name “p-value” has nothing ...
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