Maybe the colours you chose at the start don't resonate with you in the same way the did in the beginning. Can you add some fresh colour or take a colour out? Playing with colour is a fantastic way to lift your mood and bring about the excitement you had when you started the project.
Perhaps it's a long term WiP that you've been working on for absolutely ages. You know you want to finish it, but the progress just seems to be sooooo slow. By taking yourself and your project to a new space you'll find the different environment will give you fresh inspiration and energy. This could mean taking your WiP with you to the beach or the park, it could be going to a cafe and sitting in a quiet corner to work on it, or it could simply be moving to a different room in your house. The change of scene will do you good!
And then there are those projects where you simply don't like the way they're going. Have a think - is there anything you can change? Let's say it's a crochet cardigan. Perhaps you don't like the way the shaping is going and you don't think it's going to fit properly. How can you alter it? Crochet is very easy to increase and decrease to suit shaping (and if it doesn't work, it's easy to frog and start again!).
Finally, there are some WiPs that have sat so long in your pile that you can't remember why you even started them in the first place! Bring these projects out, have a good look at them and make either a commitment to finishing them (following my advice above) or the decision to pull them apart and use the components for something else.
As you know the WiP-Along is open to all crafts and I know most of you will be crocheting but these principles apply to books you have had sitting around (please don't pull them apart, simply donate them to the charity shop!), paintings that are sitting in a corner, sewing projects that you've half started etc.
Until next time, happy crocheting,