How the wheel picks
When you spin, the page chooses the answer first and then turns the wheel so it stops on that answer. The choice uses crypto.getRandomValues, the random number source built into your browser. It does not depend on how fast the wheel turns or where the animation happens to end. The wheel then stops at a random point inside the chosen segment, never on a border.
Each spin is independent. The wheel has no memory, so five yes answers in a row do not make a no more likely next time. The tally counts this session only. It is kept in the open page and clears when you press Reset tally or close the page.
Modes and segments
Yes / No gives each answer one chance in two. Yes / No / Maybe gives each answer one chance in three. The number of segments changes only how the wheel looks, because the answers alternate around the wheel and every answer owns the same share of it. With three answers the segment counts are 3, 6, 9 and 12, so the three answers always fill the wheel equally.
Questions
Is the result random?
Yes. The answer is picked with crypto.getRandomValues, the secure random number source built into your browser, before the wheel starts to turn. The animation only shows the answer that was already chosen.
Are the odds equal?
Yes. In Yes / No mode each answer has one chance in two. In Yes / No / Maybe mode each has one chance in three. The number of segments does not change the odds.
Is anything stored or sent?
No. The tally of results lives only in the open page and is gone when you reload or close it. The page sets no cookies and sends nothing anywhere.