For me it is that you are the designer (how it looks), the product manager (what to build), the developer (how to build), and the copy writer (how it will be consumed). And then when you launch the marketer and sales person too -- which I actually find are more energizing since you're primarily operating at a higher level than sweating the finer details of product and tech.
At least during product development, I find wearing all those hats simultaneously taxing. How do you deal with it? How do you at once zoom into the design and step back to review the copy, then switch into what to build and dive into how to build it?
Yeah, this is tough. But also incredibly rewarding. I've spent years with my technical blinders up, thinking I could just "engineer" my way to growth. The process of taking those blinders off, swallowing my ego, and learning how to properly engage with customers has been... humbling. The shift from specialist to generalist seems to be making me a better human being, to be honest.
As for how I deal with that context switching... I'm a novice, but I have found that staying focused on one KPI (like MRR) and filtering all activity through a question, "Is this activity the best way to budge that needle?" - that's helped me stay a little more focused on the "right-ish" things. That usually ends up being some form of "talking to customers", which actually lets me set my other hats aside for the most part.
What's worked for you?
Try to separate time for each activity. For example- Morning 9-11 for copywriting, 12-4 for dev etc. That will help you to think only one way and focus more.