How many times can a component go through reflow oven?

Is there a limit to how many times a pcb with components can be run through a reflow oven before the components start to degrade?

Example: We load the SMT components on the bottom side of the pcb and run it through the reflow oven. Next we load the top side and reflow. Then we place pins (that have solder built into the pin) on the edges of the pcb and run it through reflow again. Finally, this newly created SMT module is placed on another pcb and again run through a reflow oven. That makes it a total of 4 passes through a reflow oven for the bottom side and 3 times through for the top side. The assembly is lead-free so the reflow oven is running at the elevated temperatures needed for that.

Would the multiple reflow temperature cycles cause the components to start to degrade? I would assume so but at what point or how many cycles before this happens? Would long term reliability be compromised with the 4 cycles described above? We are using IC packages SOT-23 and uSOIC-8 along with 0402 Rs and Cs. Any thoughts would be appreciated. Thanks!

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