IF we are comparing factotum with a rogue... well factotum isn't a combat class, rogue is.
All classes are combat classes. If your class doesn't offer you anything meaningful to do in combat, your class is made of fail and shame.
That's that it. The Factotum doesn't have anything all that meaningful to do in combat. Even by the almighty 8th level, and investing three Feats into Inspiration, the Factoum gains a maximum +13d6 SA
per Encounter. Or four extra Standard Actions, or Skill Boosts but no room for Knowledge Devotion & the boost is 1/day per Knowledge Skill.
To put that Standard Action into prospect, Int>Dex>Con>Str, saying the Factotum has 12 Str is generous. A +1 Greatsword means 2d6+5. Those four Standard Actions gives him a 6 Attack Nova with one point left over to SA. That's a maximum 12d6+30+1d6, or 75.5. Round 2, 3, 4, 5, 6, yeah for the rest of the Encounter he is a Commoner with an Enhanced Greatsword, 12dmg per hit.
To scale, even at two Attacks, unaugmented +4d6 SA, and spending only a single Feat for Craven (not three like the factotum) the 12 Str Mace using Rogue deals 1d8+1+4d6+8 (27.5) per hit or 55 per full-attack. Only 20 points behind the Factotum, which is made up and massively surpassed in round 2. And every single round after that just insults the Factotum's attempts. Even a Barbarian can do better.So combat wise the Factotum
must piggyback into another set of OP rules. Ubercharging, the default to all failed Classes, or Iaijitsu Focus so it's less impactful than a Rogue. But ultimately is
those rules that are the reason the Character succeeds, not the Class Features.
But wait, Cunning Surge is awesome right? You can use it to
trigger Magic Items! Problem with that is that this is literately throwing gold at Encounters in order to win. And NPC Hirelings, Familiars, Animal Companions, or basically farm animals and tertiary Class Features already handle this job of handling Magic Items for you. It's just not that impressive.
On a TO tabletop, the Dilettantes allow the Factotum to stock pile Fire Shurikens, Shrunken Items, and thinks selling Walls of Iron some how beats a Commoner crafting gold pieces for a WBL trick. These can make up the difference, but a Barbarian is ready to fight as equally on day 1 as day 12. The Cleric needs an hour, the almighty God-Wizard needs 9 hours to rape reality but the Factotum? He needs a week in between each Encounter. Which just doesn't happen in a real game, and without it they can't create the room they need to shine.