There are two things founders hear very often from experienced VCs that seem to be contradictory:
You should always be raising
You should reach out to VCs when you are not raising
If taken at face value, Statement 1 basically renders Statement 2 impossible.
On the other hand, in the art of fundraising, both statements ring true at the same time.
What Statement 1 means is that founders should be in fundraising mindset all the time - any good chance to meet a new potential investor is a chance that should be taken. Anytime a good VC is happy to squeeze out 30min for you, whether in the office or on the way to the airport, you should take the chance to get to know him or her even if you've just finished raising a round.
Fundraising is all about building a pipeline, as in a B2B sales process. The wider the top of the funnel, the more chance you'll be able to close some investments eventually.
Actually talking to VCs when you're not raising might end up being the best conversation you have with them. You're not asking for money at the moment so you're more relaxed. The VCs are more relaxed too. It's easier to build a positive first impression in this setup.
What's important is the next step: update the VCs about the progress of your startup with short, personalized emails, say, every one or two months. Show the growth trajectory. Then by the time you're ready to kick off your next round, they will already have known a bit of the growth path your company went through. That removes a lot of friction and lends more credibility naturally.
In other words, Statement 1 and Statement 2 are not only NOT contradictory, they might as well be the same statement: