Open-mind that exists along under the presence of compassion and wisdom is void of ignorance and the consequences of ignorance.
Keeping the hand away from close contact with fire to avoid getting injured/burnt is not 'bad', 'wrong', 'ill-thinking', or 'being selfish'. By not keeping the hand away from close contact with fire, but deliberately keeping the hand in close contact with fire, thinking that it's 'bad', 'wrong', 'ill-thinking' or 'being selfish' to keep the hand away from fire, and I want to be 'open-mind' where I should believe in the universe or God will protect me from any harm, is ignorance, or mere stupidity.
Being compassionate, friendly and open mind towards all beings doesn't mean that one should be ignorantly and wittingly letting oneself to be taken for granted/advantage by those with selfish intention/desire, or giving the opportunity for others to misbehave and endangering oneself to be mistreated/hurt by the ignorance of others.
Open mind towards all without judgment is more about being opened towards everyone could be kind or unkind, depending on the current state of their minds, without judgment of 'This is a kind person' or 'This is an unkind person'. One doesn't need to trust, or distrust, or mistrust anyone for anything.
This is similar to where the teaching of 'surrendering' in Yoga is also being misunderstood by many passionate minds in the same way. 'Surrendering' in Yoga is about surrendering the ego and egoism of attachment, identification, desire of craving and aversion, performing all our duties and actions without attachment, renouncing the fruit of actions, being dispassionate and desireless. It doesn't mean that one doesn't need to be responsible for one's actions and the consequences of actions, or doesn't need to be responsible to be looking after the well-being of oneself and those under one's care. Such like, driving on the road. One needs to be attentive and stay alert while driving, and be responsible to follow the traffic rules, and watching out for 'reckless drivers' or 'other road users'. 'Surrendering' doesn't mean "Ah, I surrender to God completely. Everything is God's will. Whatever will be, will be. I must not have 'ill-thinking' towards anyone that some of the drivers might be driving recklessly. I shouldn't have 'negative thinking' about there could be 'unexpected objects/animals' might be on the road that I need to watch out for. I don't need to drive carefully with attentiveness or stop at any traffic lights and junctions, and without watching out for the other road users or any unexpected objects/animals on the road, and I will arrive safely at my destination without any problem." That is ignorance, or mere stupidity.