Whether you indicate or not, other road users including non motorised ones would be wise to assume that a flashing indicator is only evidence that the bulb or LED is working, and not absolute proof of the vehicle's intentions.
Like Schroedinger's cat, there are several simultaneous states which could be true but which can't be determined until further events occur, eg turning or not -turning.
A cyclist's arm might not be extended before turning, but there's no malfunction that could cause it to remain unknowingly extended unlike an uncancelled electric indicator.
Not sure where I'm going with this. I suppose it's dangerous to assume anything, and to try not to add to the confusion by doing something unpredictable.
It used to be said when I was a newbie motorcyclist that it's the one you don't see that gets you, and that it's always safer to assume the existence of the invisible driver. Waay back then, you depended on giving hand signals so you gave a positive sign to other road users, as you do on a cycle.
Now that motorised road users take the presence of indicators for granted it can be a blessing and a curse. Good bright signal lights, easy to see. Poorly or carelessly used, an invitation to a collision. Take your pick!