Early on, doing your own marketing makes sense. Money is tight and you're wearing every hat anyway. But as the business grows, DIY marketing usually hits a ceiling. Here's where I see that happen.
Time runs out first
It's usually not skill, it's time. Once you've got a full schedule, three hours fighting a broken page layout is three hours you didn't spend on customers or closing jobs.
The "good enough" wall
DIY is usually good enough to land your first customers. Getting past that is harder. A template site and boosted posts don't hold up well against competitors putting real work into SEO and their websites.
You can't see what you're missing
When you don't know an area well, you don't know what's slipping. A technical SEO issue, a contact form losing leads, or ad money going to the wrong place. Knowing what actually matters usually takes a second set of eyes.
Tactics stop being enough
DIY marketing tends to be "post on Instagram today." Getting past the wall usually takes a plan, where each piece has a job in moving a certain kind of customer closer to calling you. Where to start with digital marketing lays that out step by step. Same goes for the site itself. Plenty of DIY builders get people launched and then get in the way, which I dig into in JSX builders, page builders, and raw PHP.
Outgrowing DIY isn't failing. It usually means the business got bigger than what one person can keep up with on top of everything else. When you get there, start here.