First of all, I need to explain to you how a smartphone battery works.
This way, you will better understand why it allows your phones to last longer. The explanations are a little scientific, but nothing very complicated in reality. The batteries of our smartphones work with so-called Lithium-ion. When the battery is charged, lithium ions move from the negative electrode to the positive electrode. When the battery is discharged, the lithium ions move in the opposite direction. It is thanks to the circulation of ions towards the electrodes that the electric current is created and supplies our telephone. What must be remembered above all is that the passage of ions from one electrode to another represents a charge cycle. And each phone has a limited number of charge cycles. Generally and with current technologies, this number is at least 2000 charges. This represents on average 10 years of charge. But over time, the battery electrodes start to wear down causing the ions to flow less well. This reduces the storage capacity until it no longer works at all.
The problem is that certain bad charging habits accelerate the natural wear of the battery.