Were the two starters new or used?
Whilst the thought is that they rarely give trouble, I have had to replaced the starter on two of mine with the same symptons on both - turn the key, ignition lights on, but then nothing when turned to the crank position. It started as an intermittent fault on both, gradually happening more and more until totally 'dead'.
Was the solenoid on both - water ingress had caused severe corrosion to the internals of the solenoid. A replacement solenoid on both AND importantly sealed with silicone to prevent further water ingress and all been good since.
Not the easiest component to remove / change due to access but quite doable. Due to this I didnt even consider fitting a used one - even if it had appeared to be serviceable. Both mine were overhauled by a long established auto electricians, for not much money.