Lots of threads you could pull here, but my first thought is highlighting the difference between a representative as a delegate vs. a representative as a trustee. The former gauges a representative on how closely they follow the will of the people on any immediate day. The latter is basically the idea that the representative should stick to his principles regardless of the whims of the public. If a free-market libertarian is elected and the public suddenly thereafter demands socialism, is it the obligation of the representative to support socialism? Or is it the obligation of the populace to vote for a socialist in the next election?
Your proposal takes representative as a delegate to the extreme. Let's walk through some likely outcomes:
1. People are fickle about policy because their preferences adjust to immediate circumstances. You can imagine some pretty incoherent voting records coming out of that system. You can also imagine contradictory policies being passed.
2. People rarely wish to take the long hard path needed for prosperity and are more likely to vote for short term relief at the expense of the future.
3. Putting every issue to a vote by the populace means people need to be experts in every field or face voting based on vibes.
4. People are unlikely to vote on every single legislative issue, meaning the boring industry specific issues are likely to be unrepresentative of the public at large and far more representative of certain interest groups. You can bet industries will vote to enrich themselves at the cost of the public.