hey there,
I believe that positive attitude is necessary not only in your work life but also in all the activities that u perform everyday...
for example,
you should have a positive attitude in your personal life, you should have positive attitude for the activities that u work on...
You should start any new tast with a positive attitude, only then you would be able to complete it effeciently...
and if a person is havin a positive attitude towards something then he is going to have High level of Confidence towards his work...
so POSITIVE ATTITUDE towards any task is a must !!!
Take care...