95% of builds on Path of Exile scale with special uniques or powerful rares
The reason it is still fun after 20+ hours of play is because of the skill and gear progression that comes with most builds in the game. 95% of builds on PoE scale with special uniques or powerful rares as well as getting gear that has more linked sockets (5 socketed and linked sockets on gear are a lot more rare than 4 linked gear, and 6 linked gear extremely rare and endgame to acheive in most cases). Both of these will change will change how the skill works/increase their damage output significantly, making you want to progress even more to see how far you can take a build idea.
So the long and short of it is yes in it's most basic form the fun of playing the same skill over a long period is to see the returns of your investment into the skill and seeing how far you can take it, which is much more rewarding than it sounds due to the sheer complexity and number of options the game has to offer.

Dec
Buy Cheap and Safe Path of Exile Orbs on Poe4orbs.com
As Christmas Day is coming soon, now you can get 3% off dicount at our site by using the Coupon Code "POE4ORBS". The Event will last from December 20th to January 20th.

Oct
Path of Exile ethical faring?
When action-RPG Path of Exile was launched last year, developer Grinding Gear Games was clear. It would be an "ethical" free-to-play without any compromises to the evils of pay-to-win.

Jul
poe4orbs:PoE 3.11 Harvest All Challenges Guide
As always, PoE 3.11 has 40 challenges for players to unlock, and every 12 challenges unlocked will get a league reward, which are footprint, cloak, and portal. This guide aims to help players in completing those challenges.

Aug
poe4orbs:PoE 3.19 Top League Starter Builds Guide
Here is latest and best PoE 3.19 Lake Of Kalandra League Starter Builds for beginner, each video guide is attached with a pob link for players' reference.

Oct
Chaos Damage doesn't bypass Energy Shield
The way I see it, unique items are bad design. They put build-enablers into a terrible binary: not enabled, or best-in-slot. There's no room for gear progression in that gear slot under such itemization.