Some people purposely match with just about everyone they find attractive on a dating app but will be more picky when it comes to actual communication.
They do this to give themselves more potential dating options, but there are always going to be matches that have a higher priority than you do. When they are already hearing from those that have higher priority, they will put matches like you on the back end.
Others ghost after a couple of message exchanges because there was something specific they wanted to experience in conversation and didn’t. They have no patience. Once they figure out that the romantic ingredient they need isn’t in the conversations, they ghost.