I think the main reason people fail diets is that they find it hard to “stick” to them. They get bored, they get cravings, they miss their old eating habits(and they also forgot who bad they felt on the “bad” diet) and they can’t be “bothered” with eating healthy anymore. And you know what, I totally understand. But saying that I only get “bored” with eating healthy when it is too extreme. Like when I am on a competition prep or even now doing the Rebuild Diet. I rather go to the shop buying ice cream and cinnamon buns than eating salad all day(and I prefer eating healthy). This is why it is so important to have a varied, balanced diet. To be able to eat the things you enjoy and still feel and look good.
If you were my client I would never tell you to eat “clean” all day. I would find out how your diet was at the time, how your schedule was, likes and dislikes and create a lifestylediet that was suitable to you and your needs(although if you were eating biscuits and pop tarts all day there would of course have to be dramatic changes). I wouldn’t ask you to make the diet work, but make the diet work for you. And this is another thing I think a lot of Nutritionists and dietician and all sorts of self-proclaimed “weight loss experts” do wrong. Everyone is different and have different needs. Some people work better with certain food groups and so on. We have variant individual needs and if this is taken in to consideration I believe this is the key in a successful happy healthy life. And not a boring diet you have to struggle your way through.