Why would a charger with higher input / output charge slower?

[AC Question]

Hello

I bought my phone in November 2015 [Sony Z5 Compact] and affter 6 months I lost the charger that came with the phone.
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Soon after, I got a new Samsung Tablet that came with a charger with an input of 0,15A and output of 5.0V - 1.0A and surprinsingly it charges my phone faster than the original charger. I don't know why but it's very fast to charge my phone.
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I have been using this charger since then but I decided to buy a second charger for emergencies. This new charger was supposed to be faster and better with an input of 0.35A and output of 5.0V - 2.0A. *It's also an original charger from Samsung.*
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However, this new charger is extremely slow. I noticed it takes up to 40% more time to charge the phone. Today I installed Ampere and now I have the proof that I needed. While the first charger (5.0V - 1.0A) measures at least 700mA and up to 1060mA, the second charger (5.0V - 2.0A) never measures more than 600mA and usually measures below 500mA.
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Why is this? Isn't a charger with a higher input and output supposed to charge faster? I tried switching USB cables and wall sockets but the results were the same.
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I am sorry for my ignorance but really wanted to know why this could be happening. I don't want to think I wasted money on an original charger that doesn't charge as fast as it's supposed to.
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Thanks and sorry for my English (It's my third language after Spanish and Italian).*

 

[B. Diddy]

Welcome to Android Central! Samsung devices can be pretty picky about the chargers they use, so it's possible that Samsung charger has some kind of special circuitry that inadvertently causes it to charge less efficiently on other devices. You could try getting a 3rd party 2.0 A charger from any store and see if it also charges slowly.

Your English is terrific! I know plenty of people whose first and only language is English, and they sound much worse than you.