botch job

A task completed very poorly, sloppily, or incompetently. Whoever repaired your computer last time did a real botch job. You're better off replacing the whole motherboard than trying to fix it now. Tony made a botch job of the Jefferson account. Sally, I want you to take over and see if you can salvage it. This government has made another botch job of reforming the tax code. Now it's more confusing and onerous than ever!