I heard a great quote today:
"The best time to fix the roof is when the sun is shining." - John F. Kennedy
This applies, of course, to many situations in life. It simply brings our attention to the fact that if we leave the roof (or issues) until it is leaking and there is a hurricane, we may lose the house (or our job, family, health etc.)!
It makes me think of resume writing, which is a daunting task; I know as I do it daily on clients' behalves. I evaluate, strategize, obsess over details. I ask many, many questions (one client asked if I'd been a police interrogator!) (the answer is no!). And then I distill mounds of info (one client sent over 70 pages of supporting documentation) into a two or perhaps three page resume.
If you are leaving your resume until you are let go, downsized, outsized or otherwise terminated, you are leaving it too late. At that difficult time, tackling a resume is an onerous task, not a career-boosting project. Doing it right is a project, for sure. Even working with a professional, like me, should take time - you can't distil a person's abilities, skills, talents, education and experience in a quick interview.
The internet abounds with conflicting information about resume writing. Make sure you work with a trusted individual with credentials, like the ones that I have earned through Career Professionals of Canada. (I am about to renew for my fifth year of membership; thought I'd give them a plug!)