I am an employer and here's the deal. Like many others here have said. Give it your all or none at all. Here's why. These days your work history is a simple click away for future potential employers. You can't outrun a negative review of your work ethic. It's too bad too. When I was coming along in the 60's and 70's I burned some serious bridges that would have closed a lot of doors for me in this Information Age. Always give your best performance if you want the best employment opportunities in your future.
And get off my lawn!