That’s also almost my experience, but for me “learning while working on a problem independently” applies in all phases about equally. I haven’t tried “learning while collaborating with people” at novice level, but it’s well possible that it’s useful.
When first starting out: learning while collaborating with people.
When going from beginner to intermediate: learning while working on a problem independently.
When going from intermediate to expert: learning from reading previous work/existing codebases
That’s also almost my experience, but for me “learning while working on a problem independently” applies in all phases about equally. I haven’t tried “learning while collaborating with people” at novice level, but it’s well possible that it’s useful.