How to handle datastore failures?

So say this is my data that I would like to store, now I've read the info on the wikis about failures but since this doesn't auto save, how would I make sure a player gets notified that their data may not save? Should auto saving be implemented or not? And how would I make it so that if, in fact, the data may not save that it doesn't overwrite the players save file? Not understanding how to do this.

local ds = game:GetService("DataStoreService"):GetDataStore("stats")
statz={"Kills","WOS","Noobs"}
game.Players.PlayerAdded:connect(function(plyr)
    local a=Instance.new("NumberValue")
    a.Parent=plyr
    a.Name="leaderstats"
    for i=1,#statz do
        local stat=Instance.new("NumberValue")
        stat.Parent=a
        stat.Value=0
        stat.Name=statz[i]
    end
    local child=plyr.leaderstats:GetChildren()
    for i=1, #child do
        child[i].Value=ds:GetAsync(plyr.userId..child[i].Name)
    end
end)

game.Players.PlayerRemoving:connect(function(plyr)
    local child=plyr.leaderstats:GetChildren()
    for i=1, #child do
        child[i].Value=ds:SetAsync(plyr.userId..child[i].Name,child[i].Value)
    end
end)