Exterior wooden door - varnish, other protection?

[rossyl]

Hi All

I've got an exterior wooden door on a garage that sees a lot of weather.

I used Sadolin Classic Wood Protection and frankly wasn't impressed:
- the door would get wet and swell.
- the door also darkened with what looks like almost mouldy finish.
So it went from a deep dark wood colour, to a mix of grey wood and blacker areas. I wasn't impressed with Sadolin Classic Wood Protection.

So what should I use instead?

It sees a lot of rain.
It's North East facing, so a bit of sun, but not loads.

Any product recommendations?

Thanks