Opinions...Lamborghini or Mini minor?

i think it might just be a case of wrong horse wrong rider. i believe they should both be on the same level of what they want to do such as showing, jumping etc (you wouldn't use a grand prix horse as a happy hacker after all) some horses can be overly sensitive and know how much they can get away with with each individual. for example i have a 16.1hh chestnut TB dressage mare (shes a complete stereotype) she is so sweet with me and very well behaved. but when my 8 year old niece trys to groom her she completely changes she won't stand still she starts picking her back feet up at her (never kicked out) shakes her head and bares her teeth but the second i come back over shes back to normal. horses are a lot smarter than what many people think! but i believe especially with younger riders more time and consideration should be put into finding a 'perfect' first horse to match its new owner, which after all is essential for a successful partnership