It's wise to learn by doing things that interest you and picking up the required skills as you go. It may be wise to avoid wasting time learning things you haven't encountered a need for that are on somebody's list of "stuff you should know" since there's legitimate disagreement over what people should know, and you only have one lifetime. A potential problem is that you may not know what it is you're missing until you learn it. A lot of CS fundamentals are like that; I recently saw somebody invent association lists in C# because he didn't know what a hashtable was. Just in time learning is a useful idea, but dangerous. Use it, but not to the exclusion of all other methods of deciding what to learn, and be careful with it.
Wise words spoken by the foolish are foolish.
It's wise to learn by doing things that interest you and picking up the required skills as you go. It may be wise to avoid wasting time learning things you haven't encountered a need for that are on somebody's list of "stuff you should know" since there's legitimate disagreement over what people should know, and you only have one lifetime. A potential problem is that you may not know what it is you're missing until you learn it. A lot of CS fundamentals are like that; I recently saw somebody invent association lists in C# because he didn't know what a hashtable was. Just in time learning is a useful idea, but dangerous. Use it, but not to the exclusion of all other methods of deciding what to learn, and be careful with it.