Why do the start and end section of some strokes are missing or thinning out?

I couldn't find any stroke settings to set the full stroke lenght to uniform width, indifferently of stroke pressure (obviously, I don't use a digitizer and pen, only a touchpad / mouse), or stroke speed.

It seems that some strokes simulate stroke pressure, or are they only affected by stroke speed?

I want strokes of uniform width, only, for the full lenght of strokes.

Can this be set universally for all strokes in Illustrator?