For example, if someone announces that they are learning to paint in watercolor, don't recommend that they learn oil paints.  "You know what would be a really hard thing to learn? Oil painting!"

If someone shows you a wooden chair they made from scratch, don't recommend that they add handles. "Nice, you should add handles!"

If someone enthusiastically says they just bought a Ford Ranger, don't start talking about how great the Toyota Tacoma is. "The Tacoma is the real best truck, it blah blah blah...."

These "helpful recommendations" are not helpful. Whenever I talk to someone who recommends something like this to me after showing them something I've been working on, it comes across as intrusive, controlling, and unappreciative.