How did anyone not suspect that Tris was a Divergent during Dauntless Initiation other than Four?

Question

When it came to the part where the initiates had to jump off a cliff into a hole in the ground (which held a net to the entrance of the Dauntless compound), and this is after they all jumped off the train, Tris was the first to jump and she was Abnegation which Four himself said was 'unheard of'.

When this happened, why did no one suspect that Tris was Divergent, not everyone (especially Christina who was a Candor) would have taken that bravery to make the first jump.

Four (Tobias) found out after Tris had smashed the glass box entrapping her in an illusion and realised she was, Tori found out during the aptitude, I know that Eric realised later during Intiation, but why did no one suspect when she was the first jumper?

Answer 1

Because the test result is a secret, so most of them assumed she's Dauntless

The way the simulations work is that in the given scenarios, each stage should eliminate at least one or more of the factions, ultimately eliminating at least four factions and leaving out one as the result. The result is entered into a system which is only accessible by a select few people. The teenagers are not supposed to discuss their test results, at least until after the choosing ceremony the following day. However, it is expected that they take the results into account when choosing their faction but this is not enforced as they can still choose any faction, regardless of their test result. Source

And there was a scene where Tris was talking to Jeanine and Tris was surprised that even her knows her test result.

Also, in the same conversation between Tris and Jeanine, Jeanine said to Tris that what she did is impressive (Joining Dauntless despite her test result)

• You made an impressive choice, Tris, despite your parents. And your test result.

• I'm glad you were smart enough to know your own mind.

So it seems like the one/ones who know about her test result, thought she made a brave choice and trying to fit in and go toe to toe with the "real Dauntless", and they (or at least Jeanine) think what she's doing admirable.

Answer 2

I believe that noone suspected was because they just thought that she either wanted to get the jump over with or because she was abnegation, which means selfless in the faction system, they thought that she was just trying to show everyone else not to be worried.

Another reason could be that they just thought that she was being cocky as you might have seen, after she said 'me', some girl put their hands up as if to say, you go do that then.