Be cautious with paid growth, as it can be risky; if you pay for users who don't generate enough revenue, you could run out of money.

It's important to view paid marketing as an accelerant rather than the core growth strategy, focusing on organic growth as the sustainable foundation.

Relying solely on paid acquisition for growth is risky. If your growth depends only on ads, it may not be sustainable in the long run, especially as competition increases.

The best companies grow through word-of-mouth rather than paid acquisition, and in the early days of a startup, if you lack funds, focus on growing your business without spending money by doing things that don't scale. This organic growth is a sign of a strong product that resonates with users.

Organic growth, which is growth that doesn't require payment, is often neglected by founders. For example, at Monzo, we reached a million customers before spending on direct marketing or advertising, primarily through virality and network effects.

As a startup grows, the focus shifts from just acquiring users to ensuring sustainable growth and revenue. We learned the hard way that even if users love our product, we must also pay attention to our overall growth metrics to avoid becoming a beloved startup that fails due to lack of financial viability.

When considering growth channels, focus on how users discover your product. For small companies, it's often too early to think about scalable growth channels until you have a solid user base.

In the early days, focus on product retention rather than just growth. If your retention rate is low, prioritize improving your product before trying to scale.

There are three types of growth: sticky growth, which focuses on retaining existing users; viral growth, which relies on users referring others; and paid growth, which involves spending money to acquire users.