I have to make sure I workout as soon as I get home from work, if I sit down of think I'll just put my feet up for 5 minutes, I never get up again.
Yup! If I don't exercise in the morning the odds are very great that it will never get done that day.
Here's my take.
If you are performing an activity that challenges and excites you, something that you
want to do - it doesn't matter what time of day you exercise! If you love it - you'll find a way to fit it in your schedule.
If you dread whatever exercise regimen you're following (first thing that comes to mind is running on an indoor treadmill

) - it's only a matter of time before you'll start making excuses. For these people - either get the "pain" over with as early as possible and exercise in the morning-before the excuses can start - or change what you're doing!!
I go back and forth with my motivation. What I use to keep me on track is the
Endomondo app. I have the free version on my iphone. It calculates how far and how long I've walked, run, rode, swam, hiked, strength trained, etc....gives me the caloric expenditure and a number of other measurements. For some reason this really motivates me.