We all probably lived long enough to hear that the only way to do great is to love what you do. If you are younger, you might not pay much attention to it but as you get older you really start to believe these words.
First of all, passion is the thing that makes people ambitious and determines them to keep going. Without even the tiniest bit of passion, you can feel burdened by the amount of work you have to do. You might even give up if you feel that the stress has gotten to you and you might really be conflicted about what to do.
Also, if there is no passion then you will just try to do your work as fast as you can just to get it off your mind. You obviously will finish what you are doing, but that doesn't mean the result is all too pleasent. People can get very judgemental and critical about your work ethic and even question your abilities.
In conclusion, you need a driving force first to actually have good results and to feel satisfied with your hard work so try to pick up new hobbies until you find something that suits you.