In the TastyTrade video below Tom discusses making it a goal to collect enough premium that it will add up to 40% of the width of the strike. He also reviews some examples of successful trades and states that typically 67% success rate is an average target to shoot for.
Example: If the spread on the strike is $5 look to collect at least $200, if the spread is $1 look to collect $40.
Another great point of the video were results discussed on three stocks and how the overall success rate was higher when IV was high (using further OTM options) and at least and IV at 50% or greater.
Screen Shot: Trade Results when IV is high
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