This is a major red flag that the firm isn't sufficiently serious about hiring and I would always walk away from a firm without a clear idea of their needs and

This is a major red flag that the firm isn't sufficiently serious about hiring and I would always walk away from a firm without a clear idea of their needs and the number of rounds. My experience with a firm that started with three, then paused, had an "open evening" for interviews and then wanted more (which I politely declined and privately blacklisted them) reminds me of the lucky escape I had: the firm went through this mess only to uncover (a little later) an operational error that left them refunding several billion to clients, trundling on as a zombie firm!