I think it’s very good for a young person to work hard full time while they are young and have the energy to do it.
Growing up my father advised me to get good employment and invest as much as I could throughout my working career. He had a saying that I have passed on to others, "Savings and wise investments are stored labor." I have seen way too many who followed the idiotic (IMO) advise of the users at the top of the JW hierarchy to only do the minimum amount of work to scrape by, and they are still doing that when they are crippled old people and finally drop dead in the harness.
I followed my father's advice, and was able to retire in my mid forties and still live comfortably. My investments are providing me with the same income every month now that I was earning when I was employed full-time. I've also seen that the following scripture is true for most JW's who obeyed the "don't get any extra education, don't work full-time, don't store up treasure on earth (savings) are having the same end results.
(Proverbs 6:6-11) 6 Go to the ant, you [uneducated] JW; see its ways and become wise. 7 Although it has no [governing body, governing body helper, or elders] 8 it prepares its food even in the summer; it has gathered its food supplies even in the harvest. 9 How long, you JW, will you keep refusing to get an education or a good job, or savings? When will you rise up from your recliner? 10 A little more study, a little more preaching, a little more washing of the windows in your desire to obey eight men in New York, 11 and your poverty will certainly come just like some rover, and your want like an armed man.
Edited to reflect the way I view today's typical JW