[rwmj]

You certainly have more of an "impact", but that might be just that everyone hates you.

However I'll go with the nugget of wisdom in your post: Some coding involves lots of hard work to small parts of a program, so you don't have much overall impact on the product.

This is typically because you're doing it wrong. You're either using the wrong language (eg. C for a GUI product), or you're reimplementing wheels when you should be using a library, or you're not able to inspire others to join the project and help out on some details.

Or, very very rarely, what you're doing is ground-breaking and highly skilled. You can only write one line of code each day because it needs so much thought. This is not something that one often associates with "architect" and "program manager" in an organization.

[Evbn]

Hmm, the most popular GUI apps on the planet: iOS, Windows, MacOS and Linux apps, are written in C.