why does "<%=variable%>" html encode the results?

I want to use <%=%> to set the href value of a meta tag. 
When i do this: href="<%=variable%>" the result in the browser is this:
"&lt;%=uri%>"
If i use 2 dbl quotes ""<%=variable%>"" it then outputs the value of variable, but it also wraps it in two double quotes, like so:
href=""my string value""


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