What are the benefits and disadvantages to Lasso, Ridge, Elastic Net, and Non Negative Garrotte Regularization techniques?

I am implementing these four regularization techniques for linear regression of stock data in MATLAB but i noticed elastic net is just the sum of Ridge and Lasso, and i dont full understand how exactly Non Negative Garrotte Works as a regularization technique.

How does Garrotte work and why wouldnt you just always use elastic net over lasso and ridge? (Aside from computation complexity)