A difficult question for me to answer, if I am to be both honest and constructive. As others have said, or at least implied, there are several reasons for wanting to wear 'high heels'. (I will not attempt an exhaustive definition but, as a working one, let us assume anything greater than a net 2" (after deducting any platform) and regardless of heel style/shape. In other words, a heel that would rarely be found on any male footwear other than some cowboy or Beatle boots.)
One may wear such 'high heels' for reasons of any one or more of the following: (a) comfort/health - although Cali's need is probably rare; (b) boosting ones height, if appropriate; (c) style/appearance; (d) feeling - which may or may not include some form of arousal; (e) simple desire to wear 'girl's shoes'.
This last reason (e) is the most complex; is it because one gets a thrill from wearing something essentially feminine in otherwise male mode, or as part of a wider (or possibly complete) adoption of feminine clothing and appearance? And is it the feminine appearance of the footwear that is paramount, or simply the fact that it is daring/exciting to wear something 'borrowed' from women?
There is clearly a big difference between, say, a man in (i) a 3" block heeled boot (which would often go completely undetected when worn with trousers); or (ii) a 5" stiletto sandal (which would be obvious almost regardless of other clothing). And, whatever the style of footwear, does the male wearer wish to conceal it, or to wear it openly?
I can only say that, as far as I am concerned, I have long been an admirer of 'high heels' , worn by women, and of feminine footwear (such as strappy sandals) generally. I have always wanted to wear such footwear myself, mainly for the look and apparent feeling but also, to a modest extent, because it is daring to do so. (I have little desire to wear any other feminine clothing, beyond perhaps a private and experimental 'dressing up' session out of curiosity, which has never happened.) However, availability, comfort and discretion limit my ideal footwear styles and my activity when so shod - perhaps more than I should wish. A heel of less than 3" does very little for me, although I have some men's boots with Cuban heels close to that which I can and do wear openly. I can comfortably (and discreetly) wear boots with a 4" block or semi-block heel, and also, with more care, my Miguel Jones 'cowboy' boots with 5" heels. I would love to be able to wear stilettos (ideally around 5") as man in public but the reality, having tried, is that I cannot do so comfortably or without risking detection and ridicule. And the latter really precludes wearing lower stilettos too.
So, I guess I must conclude that, for me, anything less than a 3" heel is of little interest unless the footwear has other attractions, in which case it might be very flat. And anything much more than 4", especially if a thin heel, is mostly impractical, however desirable.