How come everyone is getting good signals?

I'm getting 3G (not full bar) in PJ and Subang Jaya / Glenmarie area. Got one shop even no signal.

The 3G is spotty. It's data transmission has some sudden stop not continuous. I can't get good 4G signals in PJ. My U Mobile even though have limited 3G and LTE, I can get constant data transfer when I have it.

I also think of porting out from Celcom, really the data connection is super not stable in KL/PJ/Shah Alam. I was from Maxis, but their current plan really not competitive as other telcos. SM50 with 2GB, whereas if Digi SP50 can get 3GB with free calls and SMS.