Reasons for becoming a citizen:
Some of us lead such righteous, law-abiding lives, certain all our business dealings are so above-board there is no chance of trumped-up criminal charges let alone there being a risk of being guilty of crimes for which six months or more of imprisonment might be imposed, there is no worry about potential inadmissibility and loss of PR status. But many of us, in contrast, are not so righteous, and almost all of us can slip at some point in our lives, a driving while impaired resulting in a serious injury accident for example, a dispute or conflict with someone leading to accusations, exaggerated or otherwise, for another.
But those who have children should be particularly cognizant of the risks of inadmissibility for criminality. The IAD decisions are rife with sad, sad tales. PR came to Canada as a young child with immigrating parent. For whatever reason, parents did not go through the process of getting the child citizenship. In his mid to late teens the child has some minor criminal entanglements, ends up on probation. Once on probation, a grant of citizenship is prohibited and the time does not count toward presence. Years pass before the PR becomes eligible for citizenship, and the PR slips again, still something minor, but if there is a period of probation of two years, that will mean the PR has to wait two more years before starting over for time to begin to count toward being eligible for citizenship. The number of PRs who end up perpetually prohibited from citizenship because of occasional, and often rather minor criminality, who came to Canada as a child, who have never really known any life other than that as a Canadian, is remarkably high. And then there is a more serious slip. Maybe it does not happen until they are in their 30s or even 40s, and in the published cases I have seen some older than 50. Sill not exactly a major crime. But with a history of minor offences, a medium-level offence can mean a formal sentence of six months or more. Then IRCC issues an inadmissibility report. There is a hearing. A real lot of these cases have very sad outcomes.
Unfortunately, those mostly affected tend to have some learning or mental health problems, autism appears all too often involved, and those suffering from bi-polar depression, or anxiety disorders.
Immigrants with non-citizen children should seriously take into account the risks their children could face long-term if they fail to take the steps toward getting them citizenship. In this regard, at least Bill C-6 has opened a path to citizenship for children which is not totally dependent on the eligibility of the child's parent.
Otherwise, there is the hassle of applying for a new PR card every five years:
Note that Canada has made the application for new PR cards almost as onerous as applying for citizenship. I am associated with some long, long term PRs (PRs for decades) who recently decided it was time to become a citizen because of the inconvenience involved in having to periodically re-apply for a new PR card. This has become an issue particularly with the eTA requirements making it more inconvenient for PRs with visa-exempt passports (the long term PRs I know are mostly UK and European passport holders).