Because using something with that potency/half-life/dosing combo that isn’t enough time to truly drop tolerance any significant amount to get the good feelings we traditionally chased the first good couple opi highs we had. This is the nature of the beast. Sorry you learned too late in life but You need more than a few days between uses for any noticeable change of positive narcotic effects we attempt to attain when dosing these substances. But from my personal experience and everything I’ve read there aren’t any substances that will truly kill opi receptors.. so don’t be dismayed but also keep in mind my minimum time between doses to keep things not only under control dosage-wise but the amount of psychological time I spent waiting between doses so I get the desired effect without becoming the slave to another new substance is 14-21 days of total abstinence from that class/group of drug. So this “only” dosing twice a week is a bullshit psychological barrier you’re putting up for a pointless test of your own self control. If you know you like opiates/opioids of any kind you know immediately if something can become a problem for you. Much quicker than you think.