Having recently watched the documentary World War 1 in Colour, I'm kinda baffled that the allied commanders kept sending hundreds of thousands of men into their deaths by charging them into German lines.

I get that it was about 100 years since the British had been to war and that war was a very different kind of game in 1914, but one would imagine that they would consider trying something differently after the first few failed attempts.

Tanks didn't show up until late 1916 AFAIK (and wasn't really effective until mid 1917), but there has to have been other options opposed to what was going on during 1914 and 1915.

What about landing in Denmark? Netherlands? Belgium? Was any sort of tactics like this ever considered?