Not really sure why you are being downvoted. My own experience aligns with what you are describing. For most residential work a homeowner can do a solid job as long as you are handy and willing to spend a little time familiarizing yourself with building codes and the appropriate techniques. Being a professional means being able to estimate accurately, meet those estimates, manage multiple jobs, etc.

If timeline isn't the most critical factor a homeowner can do an excellent job. Often even better than the professionals because you will be willing to spend extra time and attention to get everything perfect.