One told me that he worked since age 8. Not being allowed to work put him in a completely alien position. On top he was now living from other people's money, like children, old people, handicapped or sick. He was enraged by it.
He kept repeating I've worked 7 days for 30 years, I don't know how to sit on a sofa the whole day. He was getting weak, lost appetite, couldn't sleep. Every day was supposed to be a challenge rewarded with food for your family and a warm bed.
He was 3 months into the process and was clearly going insane.
The real problem is that there are several contradicting ideas at play. You can help people but you do have to employ and tax them asap. If we can't do the work the conveyor belt must slow down. You can house people but you do still have to house everyone. You can't help people by giving them other people's houses. You can assimilate people but speed and quality decline at scale.
You can tax to death and shut down social gathering, clubs, pubs, restaurants and libraries to prevent people from organizing against your sinister agenda but your assimilation capacity will greatly suffer. You must choose one.
How many natives get angry should also play a big role. Angry people are poor assimilators.
There is also a national security angle. If foreign parties want to organize a civil war for you you don't have to make it incredibly cheap and easy. To much nationalism is an ugly thing but the opposite can end the country.