Increasing a value. One script fails, the other works. Why?

Here is the script that works:

local repStore = game:GetService("ReplicatedStorage")
local re4 = repStore:WaitForChild("RemoteEvent4")

local function diamondIncrease(player)
	player.leaderstats.Diamonds.Value = player.leaderstats.Diamonds.Value + 100
	local character = player.Character
end

re4.OnServerEvent:Connect(diamondIncrease)

Now, here is the code that fails. The only difference is how I reference the value of the diamonds which is a child of the leaderstats folder beneath the player. Note that the event fires on the client side whenever a click is detected in the game.

local repStore = game:GetService("ReplicatedStorage")
local re4 = repStore:WaitForChild("RemoteEvent4")


local function diamondIncrease(player)
	local leaderstats = player.leaderstats
	local Diamonds = leaderstats:FindFirstChild("Diamonds")
	diamondsVal = Diamonds.Value
	Diamonds = Diamonds + 100
	print("You have this many diamonds.. " .. Diamonds.Value)
end

re4.OnServerEvent:Connect(diamondIncrease)

I appreciate any help. Thanks!