Some companies offers 2 weeks retrenchment pay for every year work, and additional benefits ie free medical when youre close to your retirement going forward, and you get some UIF, not much. So it depends.
If you are wise, then staying at a company longer can be beneficial
If you hop and skip, you never really get any retrenchment pay. If you are wise, it can be a lot.
My one boss worked 32 years at my company. He took early retirement (retrenchment). They paid him 16 months of retrenchment pay. It worked out over a million and a bit. He paid off his house, bought a new car cash. He had a second properly renting out to doctors getting R16k per month rental income. He got UIF for then about 9 months or so, which wasnt much, but it was a bit. His medical aid forward was covered by the company indefinately as part of the retrenchment package. Your first R500k once off is tax free too.
He now works at another company but he is set up, and just bought another apartment which he stays in, while making R32k now per month rental income, over and above his pension.
So if you are wise and invest it well, then you dont have to stay long, but if the benefits for retrenchment in the long run is good, then it may be worth hanging around.
Companies goes through changes all the time. You will enjoy your dull moments.