@ProudIslander ooh I heard my name. Hope you don't mind me butting in. I can appreciate @rebelgirl41's view. It's not really a case of not giving writers a chance. Think from a reader's POV: after you've invested in emotion for the characters, you turn the page, only to find... There is no next page. The story never updates again and you never find out if Ellie saves the world or if John got together with Anna. It's very frustrating and disappointing. It's very often the case on Wattpad with writers who aren't used to churning out finished stories so the writers often lose motivation or plot ideas halfway through, and then abandon the story.
Having said that, as a writer, there is nothing more encouraging than readers giving lovely comments as you write. It's so motivating and such a pleasure and honour.
Some readers like to be right up to date and follow the book to the end; others like to read without the writer potentially holding up the story with writer's block or real life events or just the natural pause between updates. It's just different tastes and often readers fall into one of the two categories.
You'll find if you consistently finish your stories, eventually readers will jump ship and start following your ongoing one because you're very likely going to finish yours. Also, when you finish your story, you'll get a new influx of readers who, like Rebelgirl, prefer finished ones to ongoing projects.