For me, it would depend how old you are, reasons for separating, timescales etc.
Eg, my partner was married for 20+ years. They split up because his wife ecame am alcoholic and cheated on him (i know this to be true - i know his friends and his childen and have met his ex wife all of whom confirmed it). He was a good dad then and continues to he a good dad now amd has a positive relationship with his ex.
He met his next partner a couple of years later. They were together for 10 years. They didn't marry but could quite easily have done so. Their relationship suffered for many reasons beyond their control and they split up. I met him when they were a couple so I knew her too. It was a good relationship until it wasn't anymore.
He and I have been together for two years. He is a good, kind, compassionate, loyal, loving and hardworking man.
I might feel differently though if he were 29 and getting divorced for a second time. That would suggest impulsively and poor decision making.
The bottom line is that I would take the wider context into consideration. I certainly wouldn't write someone off for it at my age or older (late 40s) but I'd want to know the details if I were younger and looking for someone to build a life and start a family with.