If the only country you're a citizen of is Canada then the government should never take your citizenship away under pretty much any circumstance. To be stateless is to be completely screwed, regardless of how often you visit the country of your citizenship.
If you have dual-citizenship, then fair enough, but a lot of people are solely Canadians and live in other places for extremely long periods of time. You can't take away someone's citizenship just because they don't come back to the country every 10 years or some other non-related rule. Being a citizen of Canada shouldn't mean you
have to come here every x years... citizenship is a right, not a privelige (as far as I'm concerned).
Under current law there is no provision for involuntary loss of Canadian citizenship except:- naturalized Canadians can be deprived of citizenship if convicted of fraud in relation to their citizenship application, or their original admission to Canada as an immigrant
- second-generation Canadians by descent may lose Canadian citizenship automatically on their 28th birthday if they do not meet the requirements for retention