The greatest threat to an ENFP's success is wasted potential. We ENFPs have so many ideas! projects-we-want-to-do! Ways to save the world!--and some of these are ideas are really very brilliant. However, we often lack the focus and stamina to develop those ideas and bring them to practical use.
Practical. That's not a word we ENFPs are thrilled about. Party, however. Now, there's a word we can DEFINE. We ARE the party, hello!
Point is, we ENFPs usually need a few "J's" in our life (ISTJs, ESTJs and even the dreaded ENFJ) to help us. These "J's" will probably drive us bonkers. But if we allow ourselves to stay annoyed with these people, we will only end up sabotaging ourselves--and the possibility of seeing our great ideas come to life.
Speaking from experience, it's important for me to feel all my feelings, but then I have to move past my initial frustration and try to understand the "J's" in my life. If I can regulate my feelings, I am able to see that "J's" have great systems and methods that can actually help me.
However, the "J's" must NOT over-react to us. A sensible "J" will allow the ENFP some "feelings-space" to go dither, play, recreate and blow off her frustration. The "J" should NOT try to micro-manage the ENFP or give her all the Rational Reasons about why her feelings are invalid. VERY IMPORTANT: The "J" should not issue marching orders or hard deadlines.
Just let the ENFP go have her feelings and maybe even offer her a cookie while she's at it.
"J's" are often tempted to view an ENFPs "outbursts" as signs of immaturity. But they are not. ENFPs are very sensitive creatures and capable of accessing deep emotion--this is a gift, not a weakness! When an ENFP chafes against rules, it's because she despises meaninglessness. Red tape and bureaucracy are the quintessential ENEMY of an ENFP soul and an ENFP would rather abandon her own project altogether than let it succumb to a soul-crushing system.
ENFPs live for the passion and beauty of life--but they also NEED systems in order to see their beautiful potential come to full fruition. So, in order to get the job actually DONE, an ISTJ is best advised to make the system and method APPEALING.
The key is simplicity and lots of built-in-rewards: preferably playtime breaks and public affirmation/acknowledgment when the ENFP produces valuable content or completes tasks on time.
An ENFP will work hard if there's a party to look forward to! But an ENFP will despair if, upon finishing a project, there is no public thanks or acknowledgment.
While an introvert "J" does NOT want public acknowledgment--a private thanks from a superior is more valuable to, say, an ISTJ--the ENFP absolutely THRIVES on awards, prizes and accolades.
An ISTJ may not understand why these celebrations are important to an ENFP, but he doesn't have to understand. He just needs to show up. A "J" who shows his appreciation for an ENFP will find her happy and motivated to get the job done.
And even ready to start on the next project!