problem can be due to lack of motivation or improper diet...you can figure it out best...
Do you know for sure it was just laziness making you tired during workouts? Because working out usually gives people more energy - it's normal to experience tired muscles but it's a pleasant tiredness. A tiredness that causes you to quit your workouts may mean there's something wrong, like perhaps your immune system is trying to fight off a cold or an infection. There are a number of physical reasons that can make someone too tired to workout.
Overtraining can make someone particularily tired and fatigued during workouts, it also decreases strength and endurance because your muscles get very tired from never having a chance to rest.
Maybe you were working out every day. If so, next time you start working out, make sure to take rest days or at least make sure to not work the same muscles day after day.
I don't know anything about what your workout was, and what your nutrition and lifestyle was like.
If you weren't eating or drinking right or were lacking on water, salts, electrolytes, potassium, protien, carbs, and other things in your diet it can make you very fatigued and weak so that you can't perform your workouts.
So make sure your nutrition is in order.
If you are really just lazy, you could just be unmotivated, which means you are forcing yourself to do something you aren't into. So look into a new form of physical activity that you can be excited and passionate about. There are many fun ways to stay in shape.
Besides, it is good to change it up every now and then.
Laziness is different than being tired. If you are lazy, then you just have to find something you like doing and commit to it. Maybe look into depression as being a reason that is holding you back from wanting to do anything.
But if you are tired there could be all sorts of reasons and even health problems that could be causing it, so ultimately I'd advise you to go see a professional.
You can do things to boost your energy, such as take supplements, Tulsi Tea, hydrotherapy, etc.