I have three questions in a survey that are supposed to measure different constructs. However, I have my doubts if the respondents will not confuse them. So, I know that Cronbach's $\alpha$ is used to check if different questions pertain to the same construct, but I wonder if it is reasonable to use it in the opposite way. Thus, if Cronbach's $\alpha$ returns something below 0.6 (poor) I could consider that those questions do not pertain to the same construct.
The questions are ordinal Likert scale as follows:
How do you think it was to find the information in the briefing?
(5) Very easy
(4) Easy
(3) Neutral
(2) Difficult
(1) Very difficult
Is the briefing interface clear and understandable?
(5) Strongly agree
(4) Agree
(3)Neutral
(2) Disagree
(1) Strongly disagree
Does the briefing look reliable?
(5) Strongly agree
(4) Agree
(3)Neutral
(2) Disagree
(1) Strongly disagree