I guess when someone puts their own fate and future in the hands of some unknown entities, they become quite vulnerable, particularly if they strongly believe in these entities to be in much command .
Thus even when they are not playing with the Ouija at the time, their subconscious mind keeps telling them that there are outside forces that can shape their lives. Thus fear is planted.
I have conducted Ouija sessions when I was both confident, and courageous and when I didn't particularly feel so, and found that in the latter case at times I felt that I was being followed around by someone and actually heard scary noises that came from nowhere, not to mention doors banging and other scary phenomenon.
My point, is that if you are to consult the Ouija at all, do it either in a playful spirit ( like that of the devil's play card in the Voyager's deck ), with friends, and/or in broad daylight or in a bright room. Better yet, say a prayer before and after each session. Bid the entity goodbye when you wish to leave the session .
In all cases, you could have bought yourself a new board, which is not expensive, and do not allow anyone else to be its master/mistress except yourself.
Those were my 2 cents. . .