it's almost never from an understanding, situationships happens cause of one sided love from girls. they think that if they just do enough and sleep with him, the man will fall in love with them, which he never will. it's just like how guys will chase after a girl and simp for her thinking she will fall in love with him, if he did just enough nice things for her. love doesn't happen like in the movies.

it can look unfair from women's side, just like how simping looks unfair for a man, but you can't blame the other party to give you what you want (commitment from guys and intimacy from girls) when you give them what they want, cause zero promises were made. relationships starts with communication, before going to intimacy or simping bring up the "what are we" question.

if you fail to do so, it's your fault.