Here's an unpopular opinion for a designer to have: most websites don't need a redesign. They need someone honest to tell them what's actually broken.
I get "we need a full redesign" requests all the time, and often the real problem is three things, not thirty. So before you spend a budget rebuilding everything, let's figure out if you actually need to.
The one sign that matters
Forget the checklists. The clearest signal is this: do you hesitate before sending someone your own URL? If you feel a little embarrassed linking your site in a proposal or a DM, that hesitation is quietly costing you deals. Your gut already knows.
The measurable stuff backs it up - a site that takes over 3 seconds to load, a bounce rate sitting above 70%, a layout that visibly belongs to 2015, or anything that falls apart on a phone (which is where most of your traffic is). But the gut test comes first.
What a real redesign is actually about
A redesign that only changes how things look is just decoration. The version worth paying for touches the things that move the needle: how people move through the site, how fast it loads, how clearly it says what you do, and how obviously it points people toward the next step. If nobody's asking "what happens to conversions," it's not a redesign - it's a repaint.
When you should NOT redesign
If your site already converts and your audience isn't complaining, don't burn money rebuilding it. Fix the landing page. Rewrite the copy that's confusing. Move the CTA. I've told clients "you don't need me for a full rebuild, you need two afternoons of cleanup" - and I meant it.
The honest version
Redesign when you have a real goal and a way to measure whether you hit it. Not because a competitor launched something shiny, and not because you're bored of your homepage. If you're not sure which camp you're in, that's exactly the conversation worth having before any money changes hands.