The NDP  % of popular vote, is virtually unchanged between the 2013 and 2017 elections, just 0.15% apart. Green support went up, Liberal support down. Indicates that supporters of the Liberals, those who value a vibrant economy, went to the Greens, presumably because in addition to a vibrant economy, they want a better way of governing, more stringent environmental protections, more stringent fundraising rules and a more compassionate government, one that won't leave the disabled to live on less than $1,000 per month. 

If, as some say, NDP and Greens are more aligned in policy, those who deserted the Liberals could have simply voted NDP. They didn't. 

Greens and Liberals could complement each other, create a vibrant economy and caring government. Green strategists aren't blind to where their newfound support came from. Neither are Liberals blind to where their supporters went & the message voters sent.  

Liberals know one can't change without doing things differently.