What does it mean to obtain a negative value for the mean in statistic

where mean in my comprehension is an average value for the result of sample population being observed, which can't be a negative value.
(regarding to my question, this is true in one case of a survey outcome investigating its respondents perceptions of certain issues using several statements,that was based on 7 point equal interval scale of agreement to disagreement answers).

If all of the possible values are positive and you got a negative value for the mean, it means that you made a mistake. Perhaps you are using the wrong formula.

To find the mean, simply sum the values and divide the sum by the number of samples.