FORTH has some elegance and it's so simple that it is tempting to implement it.

However, no language should permit defining the value of 4 by 12, as there is no situation in which this can bring more good than harm in the long term.

Another issue that affects FORTH but also Perl and other languages is that they deal with a lot of things implicitly (e.g. the stack, or arguments to functions). Most people agree that explicity is more easy to read than implicit.