Q: Does Cannabis make me lazy?
A: No
I have to answer that question with a resounding 'no' unless you rephrased it to:
Q: Does some Cannabis make me lazy?
A: Yes
So in order that I can answer 'No' to the question of laziness, it is essential I am able to buy across the counter so I can know what I am getting and can choose multiple strains for different purposes. That way I can prevent the effect of any one 'type' of strain from impacting my personality too heavily. If I smoke 'couch lock' Indica strains from morning to night then I would be lazy.
But I would choose a light Sativa to keep myself upbeat and focused on what I'm doing. A stronger Sativa might help if I was trying to be creative - but some are more creative than others. I perhaps would have a nice hybrid to get high socially with friends. And a strong indica for bedtime.
In my own experience, of having a busy career for all my adult life, the long term consumption of Sativa is the crucial part in not having cannabis affect your motivation. I think periods where I've only been able to get strong hybrids and indicas are definitely phases where I've got less done.
And in addition, I think it is important to not smoke from morning to night everyday, or you will probably have to combat laziness with strong coffee!