Somewhere along the way, someone decided that reading tarot for yourself was cheating, or unlucky, or simply not allowed. It is none of those things, and the rule has a much more ordinary origin than anyone lets on.
Where the rule actually came from
The idea that you cannot read for yourself is not ancient wisdom. It shows up in twentieth century occult clubs and in the practical advice of working readers, who noticed something true and then overstated it: when you already want a particular answer, you will bend the cards toward it.
That is a warning about bias, not a curse. Somewhere between the warning and the retelling, it hardened into a rule with a spooky tone, and the tone stuck around long after the reasoning was forgotten.
What self-reading is actually good at
A tarot spread you pull for yourself is a structured way to think out loud. The cards hand you images and tensions you did not choose, and your job is to notice what you reach for first and what you flinch away from. That reaction is the useful part, not the card.
This is also the honest thing about tarot in general. It does not know your future, it does not know your coworker's intentions, and it does not know whether the offer will come through. It gives you a frame, and you bring the life. A three card spread on a Sunday evening does more for most people than any prophecy ever could.