A few sentences that's tough. I'll try. (this one doesn't count)
(sentence 1) Building your own blockchain (that no one uses) to utilise a token for your project, community or app makes no sense when you can use an existing blockchain that is fast and scalable already and where you can create a token (SMT) for almost free (1 dollar) and being able to add value to YOUR OWN token straight away while still being able to tap into all the data of the blockchain and have access to a lot of potential users already.
(sentence 2) Popular SMT's (tokens people want to have) will get value because they can be traded on an internal exchange for STEEM (the main trading pair) and will therefor raise the value of the STEEM and popular SMT's will also use bandwidth on the steem blockchain, also increasing the need for STEEM because STEEMPOWER is needed to pay for this bandwidth.