What makes a quality asset a quality asset?

So often on here I hear people talk about purchasing low risk, cash flowing, quality assets. What exactly makes a property a quality asset to you? I am sure there are some blanket truths, but I am sure each investor has things that they look for and things they avoid. Like for me I live in an area with a lot of older homes and a lot of those older homes have limestone basements not poured concrete. Limestone basements aren't inherently bad, but they have some downsides to them and is just a feature that I avoid. So please share with me and others what quality assets look like to you and maybe some things you avoid maybe just for your peace of mind or ease of management.