By the way, is NTUC group a GLC and are the career progression/pay increment opportunities good? (I am OP btw)

Is it ok to reject a signed traineeship offer?
 

Hi, I am intending to go into the data analytics field, so recently I took up a sgunited traineeship program and was offered for it (haven't sign, but HR expects me to sign by early next week). However, I also finished final round of interview for another program which has better career prospects, IMO, and will potentially expect an offer or reply next week.

If I sign this sgunited traineeship offer now and if the other company decides to offer me later, will there be any repercussions if I rescind my signed contract?

Reneging is an extremely distasteful action in my view. Anyway I wouldn’t sign the traineeship contract - it is just cheap labour you won’t be valued by the company. Doesn’t look good on resume as well.

If you know that you will be offered for the latter, don't sign it.
IMO, it is quite disrespectful and unprofessional to rescind on an offer after signing it. As you may downright be taking away a chance from someone who is very interested in that traineeship. Although this is practiced, it is against my ethics, at least for me.